An e-mail from a Pakistani-linked extremist group linked to al-Qaeda claimed responsibility.
Smugglers, drug runners and a militant group linked to Al Qaeda frequent the desert area.
An Islamic group linked to Al Qaeda is suspected, the police said.
An eyewitness told Time that the executioners were from ISIS, a group linked to al-Qaida.
Another group, linked with European Waterways, is Go Barging, based in Wraysbury, England.
The Aksa Martyrs Brigades, a group linked to Mr. Arafat's Fatah movement, claimed responsibility.
The children's father was kidnapped by a group linked to al-Qaida, shortly after filming finished.
The agency itself is an autonomous group linked to the Organization for Economic Cooperation and Development.
An Islamic group linked to Chechnya's separatists has claimed responsibility for some of the attacks.
Both Isis and Ansar al-Islam, a militant group linked to al-Qaida, have claimed responsibility for the killings.
It was an attack by two members of the Aksa Martyrs Brigades, a group linked to Mr. Arafat's Fatah faction.
