Four Palestinian civilians have been kidnapped in Egypt's Sinai Peninsula. Pictured: Smoke rises as a house is blown up during a military operation by Egyptian security forces in Rafah, near Egypt's border with the Gaza Strip, Nov. 6, 2014. Reuters

Four Palestinian civilians were kidnapped Wednesday evening after the bus they were traveling on through Egypt's lawless Sinai Peninsula was stopped by unidentified gunmen, Egyptian and Hamas security officials said. The bus, which was carrying around 50 Palestinian passengers, was ambushed while on the way from Rafah on the Egypt-Gaza border to Cairo International Airport, the Middle East Monitor reported.

"We are making urgent contacts with the highest levels of Egyptian authorities to follow up on the circumstances of what happened and we urge the Egyptian interior ministry to secure the lives of the kidnapped passengers and free them," Gaza interior ministry spokesman Eyad al-Bazoum said. He noted that the bus had an Egyptian military escort at the time of the attack.

However, an eyewitness on the bus said there was no escort and the bus might not have been taking its regular route, the report said. “Although the daily night curfew had started, the Egyptians insisted that the bus must begin its journey from Rafah to Cairo," said the eyewitness, who wished to remain anonymous.

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No group has taken responsibility for the kidnappings, but the Sinai Peninsula is a known hotbed for Islamic terrorism. The Egyptian affiliate of the Islamic State group is operating in the region and has ambitions to overthrow the government in Cairo.

A tribal chief who lives in the region and witnessed the attacks said Egyptian security forces deliberately staged the abduction in order to discredit the Islamic groups operating in the Sinai Peninsula, a report from a Palestinian news agency said. The tribal chief said he saw an Egyptian armored vehicle close to the site of the abduction and that the hostages were being held in a local Egyptian army base.

Last week, a Croatian hostage who had been captured in the region was beheaded by the Islamist State group.

Since the removal of former President Mohammed Morsi in July 2013, the terror group has killed hundreds of police and soldiers in the region.