Gaza's Hamas rulers on Wednesday night said that gunmen abducted four Palestinians in neighboring Sinai after intercepting a bus bound for Cairo airport, The Associated Press (AP) reports.
The Hamas interior ministry said the Palestinian travelers had crossed from Gaza into Egypt late Wednesday on the third day of the partial opening of the Rafah crossing.
Witnesses told AP that several masked militants opened fire in the air and stopped the bus half an hour after it rolled into the restive peninsula.
They grabbed four youths and fled the scene, according to the report.
The witnesses, Palestinians who were in the bus, preferred not to disclose their names fearing retribution. They said they believed the militants to be from the Egyptian affiliate of the Islamic State (ISIS) group.
Hamas officials are trying to determine who the gunmen are.
Egypt this week opened the Rafah crossing to Gaza for a period of four days, the first time in two months it has done so.
Egyptian authorities have kept the crossing virtually sealed since a terrorist attack in the Sinai Peninsula in October 2014, though they have temporarily reopened the crossing several times.
Sources in Egypt have revealed that Hamas terrorists had provided the weapons for the lethal attacks in October, which killed 30 soldiers, through one of its smuggling tunnels under the border to Sinai. Hamas denies the allegations.
The October attack was one of many Egypt has had to deal with in the Sinai in recent years.
Egypt has been dealing with an insurgency in the restive Sinai Peninsula, with most of the attacks being claimed by the Sinai Province, which is affiliated with the Islamic State (ISIS).
Among the attacks claimed by the group since Morsi's ouster was the assassination of a top Egyptian police general, who was gunned down as he left his home in a west Cairo neighborhood, and a bus bombing on a tour bus filled with South Korean tourists in the Sinai.
This week, Egyptian President Abdel Fattah Al-Sisi approved an anti-terrorism law that sets up special courts and provides protections to its enforcers.