Attacks on Egyptian army posts in the Sinai Peninsula on Friday which killed at least 33 soldiers were the handiwork of Palestinian militants, a senior Egyptian official said on Saturday, stressing that the "only solution" to stop such assaults was a buffer zone between Sinai and the Gaza Strip.

No group has claimed responsibility for Friday's strikes, but Maj. Gen. Sameeh Beshadi told Asharq Al-Awsat that there was “no doubt that Palestinian elements had taken part in the attacks." Egypt's President Abdel Fattah al-Sissi also said Saturday, without elaborating, that "foreign forces" were responsible.

According to Beshadi, the militants, who infiltrated Sinai via tunnels linking the peninsula to the Gaza Strip, prepared the booby-trapped vehicle which was reportedly used to attack an army checkpoint near El Arish in northern Sinai.

The use of rocket-propelled grenades (RPGs) and mortars in the second attack was proof that local militants were not involved, as they do not have the training and knowledge necessary to carry out such an attack, Beshadi said.

Beshadi, a senior official in the Egyptian Interior Ministry, was formerly in charge of security in the North Sinai governorate, where the attacks took place, Asharq Al-Awsat reported. According to him, all the large-scale attacks in the area in recent years "involved well-trained Palestinian elements."

Beshadi cited as an example a rocket attack on an Egyptian helicopter from early 2014, which killed five soldiers. At the time, the attack was claimed by Ansar Beit Al Maqdis, a local Sinai militant group, which has claimed responsibility for a number of attacks inside and outside the Peninsula, including in Egypt's capital Cairo.

Beshadi stressed that the "only solution" for putting an end to the attacks by alleged Palestinian militants was to establish a "safe zone" between the Gaza Strip and Sinai, by relocating residents in other areas.

According to the Asharq Al-Awsat report, Egyptian relocation efforts have already begun, and in recent months a number of residents of north Sinai have been relocated due to fighting between the army and militants.

Egypt declared a state of emergency and imposed a 5 P.M. to 7 A.M. curfew in the restive northern part of the peninsula after Friday's assault, the deadliest against the army in decades. State TV also announced that the Rafah Crossing, Gaza's only non-Israeli passage to outside world, would be closed.

On Sunday, it was reported that Egypt had decided to postpone the indirect talks between Israel and Hamas in the wake of Friday's attack. Cairo informed the Palestinian negotiating team that the talks could not resume at this point due to the security situation in the Gaza Strip and the closure of the Rafah Crossing.