Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

Palestinians wait for travel permits to cross into Egypt, at the Rafah border crossing between Egypt and the southern Gaza Strip, on June 13, 2015. Egyptian authorities opened the Rafah border crossing on Saturday for three days, officials said. Rafah is the only major crossing between impoverished Gaza, home to 1.8 million Palestinians, and the outside world that does not border Israel, which blockades the strip and allows passage mainly on humanitarian grounds. Egypt shut the crossing in October last year after Islamist militants in Egypt's adjacent Sinai region killed members of its security forces. Since then, it opened the crossing partially and on a few occasions to allow thousands of Palestinians to travel in and out of the Gaza Strip. Photo by Abed Rahim Khatib/Flash90

A truck loaded with cement enters the Gaza Strip from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

A truck loaded with cement enters the Gaza Strip from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

A truck loaded with cement enters the Gaza Strip from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90

Palestinian workers offload a truck loaded with cement after it entered from Egypt through the Rafah border crossing in southern Gaza Strip, on June 13, 2015. Egyptian authorities for the first time since the expulsion of Mohammed Morsi of the Egyptian presidency, allowed the entry of cement into Gaza by 2200 tons, is expected to enter seven thousand tons of Gaza within three days. Photo by Abed Rahim Khatib /Flash 90