Young Palestinians form an obstacle to be jumped over during a military-style exercise graduation ceremony organised by the Hamas movement, in Gaza City August 5, 2015. Thousands of young Palestinians joined Hamas military-style summer camps during school vacation in the Gaza Strip to prepare them to “confront any possible Israeli attack”, organisers said. (Photo by Suhaib Salem/Reuters)

Young Palestinians display their military skills during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Palestinian Hamas masked gunmen hold their guns during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Young Palestinians swing on monkey bars over fire as part of a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Palestinian Hamas masked gunmen display a homemade rocket on a truck with Arabic writing that reads, “Burning the infant is a loan, that will not get lost”, during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

A Palestinian woman throws candy on Hamas masked gunmen with their guns during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Young Palestinians march during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

A young Palestinian jumps through a fire ring as part of a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Young Palestinians hold pistols to display their military skills during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Young Palestinians display their military skills during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)

Young Palestinians display their military skills during a graduation ceremony of the Hamas, Liberation Youth, military summer camp, in Gaza City, Wednesday, August 5, 2015. (Photo by Khalil Hamra/AP Photo)