Egyptian troops and police on Tuesday raided homes in search of suspects in an attack that killed 16 soldiers on the border with Israel and prepared to close smuggling tunnels to Gaza, security officials said.

An AFP correspondent witnessed large trucks loaded with bulldozers headed to Rafah, a town on the border with the Palestinian Gaza Strip that sits atop a honeycomb of smuggling tunnels.

“There are preparations to close the tunnels,” a security official said.

Officials said soldiers and police raided several homes near the north Sinai town of El-Arish in search of known Islamist extremists who might be linked to Sunday’s attack, the deadliest such ambush in decades.

The crackdown was underway as the military held a funeral for the 16 soldiers killed when more than 30 militants attacked a border guard post under the cover of mortar fire and commandeered a military vehicle into Israel.

A medical source in El-Arish said Israel had handed Egypt six “completely charred” bodies that were in the armoured personnel carrier that drove into Israel and was destroyed in an Israeli helicopter strike.

He said one of the bodies was “probably that of the soldier who was forced to drive the vehicle.” The militants had also used an explosives-laden truck that blew up at a border post.

At the military funeral in Cairo, attended by Defence Minister Field Marshal Hussein Tantawi and senior government officials, only 15 caskets, wrapped in the military flag, could be seen.

The funeral was aired live on state television.

“Every Egyptian feels this attack was directed against them. They all want vengeance, and there must be blood for blood,” a presenter said during the broadcast.

The attack highlighted the government’s tenuous grip on the Sinai Peninsula, from where Islamist militants have launched several rocket attacks on Israel and a deadly cross border raid last year.

The most recent attack presents a challenge to Egypt’s new Islamist President Mohamed Morsi, whose Muslim Brotherhood has good relations with the Hamas rulers of the Gaza Strip.

On Tuesday, Morsi visited soldiers wounded in the attack and hospitalized in Cairo, the official MENA news agency reported. He did not attend the funeral.

After president Hosni Mubarak’s ouster in February 2011, militants stepped up attacks in Sinai, prompting the military, then in charge of the country, to send reinforcements to the peninsula.

Egypt also closed until further notice its Rafah crossing with the Gaza Strip, the territory’s only access to the outside world that is not controlled by Israel.

The Israeli army said in a statement that the Kerem Shalom crossing, which lies on the border of Israel, Egypt and Gaza and where the gunmen breached the fence, had been reopened on Tuesday morning.