Palestinian high school students show their skills in their graduation ceremony organized by Hamas Ministry of Interior in Gaza city on Jan. 14, 2014. During the exercises, male students learned how to climb down buildings on ropes, run through obstacle courses and crawl under barbed wire. (Xinhua/Wissam Nassar)

Palestinian high school students show their skills in their graduation ceremony organized by Hamas Ministry of Interior in Gaza city on Jan. 14, 2014. During the exercises, male students learned how to climb down buildings on ropes, run through obstacle courses and crawl under barbed wire. (Xinhua/Wissam Nassar)

Palestinian high school students show their skills in their graduation ceremony organized by Hamas Ministry of Interior in Gaza city on Jan. 14, 2014. During the exercises, male students learned how to climb down buildings on ropes, run through obstacle courses and crawl under barbed wire. (Xinhua/Wissam Nassar)

Palestinian high school students show their skills in their graduation ceremony organized by Hamas Ministry of Interior in Gaza city on Jan. 14, 2014. During the exercises, male students learned how to climb down buildings on ropes, run through obstacle courses and crawl under barbed wire. (Xinhua/Wissam Nassar)

Palestinian high school students show their skills in their graduation ceremony organized by Hamas Ministry of Interior in Gaza city on Jan. 14, 2014. During the exercises, male students learned how to climb down buildings on ropes, run through obstacle courses and crawl under barbed wire. (Xinhua/Wissam Nassar)