Hamas terrorists
Hamas terroristsEmad Nassar/Flash 90

Egypt detained a senior Hamas official at Cairo International Airport, security sources said on Tuesday.

Hassan Asseify, the deputy religious affairs minister in Hamas-ruled Gaza, was stopped on his way back from Saudi Arabia to Gaza after Cairo airport security found "issues in the security approval for his entrance to the country," an airport security source said. 

Asseify will remain in detention until issues with his paperwork are resolved, the security source told Reuters

A second security source said Asseify was detained at dawn on Monday. Hamas could not be reached for comment. 

The detention came a day after Egypt opened the Rafah border crossing until August 20 to allow Palestinians to travel in and out of Gaza. 

Cairo has kept the Rafah crossing largely shut since Egypt's Islamist president, Mohammed Morsi, was toppled by the army in 2013, but has occasionally opened it for short periods at a time. 

Egyptian authorities, however, have kept the crossing virtually sealed since a terrorist attack in the Sinai Peninsula in October 2014 in which 30 soldiers were killed. The crossing is kept closed due to Egypt’s suspicions that Hamas terrorists had provided the weapons for the lethal attacks through one of its smuggling tunnels under the border to Sinai. Hamas denies the allegations.

As part of Egypt’s ongoing crackdown on terrorism, Egypt established a buffer zone along the border with Gaza. The buffer zone was initially planned to be 500 meters wide, but was later expanded by another 500 meters.

In addition, Egypt has destroyed hundreds of tunnels used by terrorists to smuggle weapons between Egypt and Gaza.

However, a decision by an Egyptian court in June to cancel a previous ruling labeling Hamas a terrorist group raised speculation that relations between Egypt and Hamas may improve.