Egypt poured troops into North Sinai Thursday and Friday in an offensive meant to tackle militants in the Israeli border region, but residents were skeptical, saying they had seen no sign of anyone being killed in what they described as a "haphazard" operation.

An Egyptian military source said on Friday that the armed forces had arrested six "terrorists" in the Sinai region, after suspected Islamist militants killed 16 Egyptian border guards on Sunday and drove a stolen armored car into Israel, which was then destroyed by IDF forces.

Army commanders said as many as 20 "terrorists" had died in the offensive launched since the attack Sunday.

Egypt began work to block illegal tunnels to smuggle in guns and travel across the border into Gaza on Wednesday, work that was continuing into the weekend.

Though it closed the Rafah border crossing, Cairo temporarily opened the border for two days to allow Gazans to return home. "The crossing will be open for all travelers on Friday and Saturday," Maher Abu Sbeiha said, Palestinian news agency Ma'an reported.

Palestinians in Gaza also reported that smuggling activity in some of the tunnels under the border resumed Friday.

Egypt has demanded from Hamas that it hand over three leaders of the Salafi terrorist group Army of Islam in connection to deadly attack, London-based pan-Arab daily Asharq Al-Awsat reported Friday.

The demand came after one of the attackers' bodies was identified as a member of the Gaza-based group, according to the report. One of the men Egypt is seeking is of Yemeni origin, according to Asharq Al-Awsat.

Army gets moving, residents ask 'where?'

Hundreds of troops and dozens of military vehicles had reached el-Arish, the main administrative center in North Sinai, security sources said on Thursday.

Armored vehicles, some equipped with machine guns, could then be seen driving out of el-Arish towards the border settlement of Sheikh Zuwaid - which had been targeted by aircraft on Wednesday. The troops saluted passersby and flashed victory signs, or filmed their departure with video cameras.

But residents interviewed later in Shaikh Zuwaid and surrounding villages said they had seen no sign of fighting.

In al Toumah, a village surrounded by olive fields, one witness said he saw troops firing in the air.

"We thought they were chasing someone, but their arms were directed up and we didn't see who they were fighting with," the witness, who declined to be named, said. "We couldn't find any bodies or signs of battle after they left."

In Shaikh Zuwaid, controlled by Beduin tribal leaders since police deserted the area last year, life continued as normal, its markets bustling. Witnesses reported a military presence on the outskirts, but no fighting since Wednesday's air strikes.

A challenge for the new president

Lawlessness has been growing in North Sinai, a region awash with guns and bristling with resentment against Cairo, since the overthrow of Hosni Mubarak in February last year.

On Thursday night, thousands of Egyptians protested in Cairo in an area where the funeral of the 16 soldiers killed in the border attack was held on Tuesday, demanding a tougher response to the killings.

"We want death to those who killed our martyrs in Rafah," one banner said. The crowd closed down a main street, creating a huge traffic jam.

Egyptian President Mohamed Morsy, elected in June, has vowed to restore stability in what the military has billed the biggest offensive in the region since Egypt's 1973 war with Israel.

He has also brushed aside accusations that his background in the Muslim Brotherhood, and ideological affinity with the Islamist Hamas rulers in Gaza, might lead him to take a softer line on militants bent on the destruction of Israel.

In al Toumah village, residents said troops had searched fields and raided one house, finding nothing.

Some residents complained the army's limited actions so far - including Wednesday's air strikes - seemed indiscriminate.

"We are not against attacking militants, but the pilots have to set their targets properly because we have been subjected to haphazard bombardment which led to the destruction of homes and cars," said Mohamed Aqil in al-Goura village near Sheikh Zuwaid.

"They said they killed 20 militants, where are they? Show them to us," said one resident at al Goura.

No one has claimed responsibility for the assault which happened Sunday during the evening "iftar" meal which breaks the daytime fast during the Muslim holy month of Ramadan.

But with wide respect in Egypt for rank-and-file soldiers who are often poorly paid conscripts posted far from their families, public anger has focused on outgoing intelligence chief Mourad Mwafi.

Media outlets had quoted him as saying Egypt had been aware of a threat before the attack "but we never imagined that a Muslim would kill his Muslim brother at iftar," he said.

Residents in al-Arish welcomed the security sweep, seeing it as an opportunity to curb criminality among Beduin, including those in Sheikh Zuwaid, where many make a living smuggling goods and people through more than 1,000 tunnels into Gaza.

"We want the army to return to the border," said 45-year-old shopkeeper Hassan Mohamed. "The tunnels have destroyed the lives of people in el-Arish. We want them to hit the Beduin hard."

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