Five members of Hamas were arrested in northern Sinai recently for involvement in the killing of 25 Egyptian policemen, Arab media reported on Wednesday.

Quoting “a knowledgeable source” in the city of El-Arish, the Saudi-owned daily A-Sharq Al-Awsat reported that 11 suspects were arrested four days ago near the border city of Rafah. Three of the suspect are local residents, three carry foreign passports, and five are Hamas members, the daily claimed.

The arrests come a little over a week after 25 off-duty Egyptian officers were killed execution-style near the city of Al-Arish, after armed men ordered them off the bus they were riding en route to their base. The August 19 attack was widely viewed as retaliation for the violent government dispersal of two pro-Brotherhood sit-ins in Cairo five days earlier.

The Egyptian military stepped up its crackdown on Islamist groups in the Sinai after the July 3 ouster of president Mohammed Morsi, who hailed from the Brotherhood.

Egypt’s military establishment has long accused Hamas of involvement in the security unrest plaguing Egypt in northern Sinai. Morsi was recently indicted for collusion with Hamas to harm Egyptian vital interests, among other charges.

The source told the daily of rumors circulating in the region claiming that the Egyptian army attacked a camp run by Palestinian extremists, in which Palestinians and Egyptians were trained to carry out terror attacks in Sinai and across Egypt.

Hamas spokesman Sami Abu-Zuhri on Wednesday called the report on the arrest “lies,” claiming they were aimed at delegitimizing the Gaza Strip and Palestinian resistance to justify Egypt’s destruction of smuggling tunnels and the near-complete closure of the Rafah border crossing.