Egypt's military said its forces were being redeployed on Wednesday to press a campaign against Islamist militants in the Sinai and that 11 "terrorists" have been killed since operations were launched.

Witnesses reported seeing at least four tanks headed west, away from the theatre of operations, but troops and vehicles were fanning out near the borders with Gaza and Israel to the east.

Confusion and inflated claims have shrouded the unprecedented campaign in the lawless peninsula that began after militants killed 16 soldiers in an August 5 attack on a border outpost.

"The armed forces, in cooperation with the police, has arrested 23 people, killed 11 terrorists and wounded one since the start of Operation Eagle," the military said of the campaign involving tanks and helicopters.

"The armed forces will continue Operation Eagle to pursue the terrorists and will start on Wednesday morning to redeploy its forces to complete its pursuit of the fugitive terrorists and finish off all terrorist cells in the Sinai."

The statement contradicted earlier claims of having killed 20 militants in helicopter strikes following the August 5 attack.

The attack on the outpost, the latest in a string of Islamist militant attacks on soldiers and police in the lawless peninsula, prompted President Mohamed Morsi to sack his intelligence chief and defence minister.

Along with the military campaign, the government is now trying to reach out to Sinai's disaffected Bedouin population. Unlike the tourism-rich south, northern Sinai is underdeveloped and has become a haven for smugglers and militants.

The president's office has helped a delegation of hardline Islamists travel to Sinai to reach out to Islamists there who complain of being unfairly targeted in the crackdown.

Security forces had briefly detained nine Salafi Islamists they claimed were "terrorists."

Nizar Ghorab, an Islamist lawyer and part of the delegation, said they had approached the presidency for help and were assisted with cars to travel to the Sinai.

"It was not a presidential delegation. The Salafis refused mediation through the interior ministry or intelligence, so we approached contacts in the presidency, who helped us," he said.

Ghorab said the delegation included Islamists who had been jailed alongside former Bedouin militants, now members of a group called the Salafi Jihad that has issued a statement denying any links with attacks on security forces.

"Our visit had one objective. Not to drag innocent Salafi jihadis into conflict with the military and police," said Ghorab. "We told them we are trying to stop any violations, and meanwhile you should not react to them."

Morsi's office was not immediately available for comment.

The military campaign is the largest deployment of soldiers in the Sinai, which borders Israel and Gaza, since the Jewish state handed back the peninsula under a 1979 peace treaty that curbed Egypt's military presence in the peninsula.

Since strongman Hosni Mubarak's overthrow in early 2011, Islamist militants, drawn mostly from Sinai's disaffected Bedouin population, have exploited a security vacuum to launch attacks against security forces and Israel.