Egypt's army has sent reinforcements into the Sinai Peninsula after President Mohamed Morsi said there would be no talks with fighters who abducted seven members of the security forces last week.
An army official said on Monday that the decision followed a meeting between the military leadership and Morsi, who has said he will not submit to blackmail by the kidnappers, who are demanding the release of fellow fighters jailed over attacks in 2011.
The army has deployed at least five military helicopters to el-Arish, the largest city in North Sinai, where fighters kidnapped the troops, since last night after sending dozens of armoured vehicles and personnel carriers across the Suez Canal into North Sinai early on Monday.
The reinforcements came as unknown assailants attacked a police base on Monday.
The kidnapping of Egyptian troops has highlighted the lawlessness in the peninsula and enraged security forces, who have blocked border crossings into Israel and the Gaza Strip to pressure the government into helping free their colleagues.
Omar Amer, presidential spokesman, said: "All options are on the table to free the kidnapped soldiers."
The state-run Al-Ahram newspaper said on its website that shipping in the Suez Canal had been briefly halted as the reinforcements crossed the waterway.
"Our patience has run out," Al-Ahram quoted a military official as saying.
Morsi has met the the Grand Sheikh of al-Azhar, Ahmed al-Tayeb and, and the Grand Mufti of Egypt, Shawky Ibrahim Allam, to discuss developments in Sinai on Monday.
The president's office vowed in a statement late on Sunday.that authorities would secure the release of those held captive swiftly and safely and in a manner that will maintain the state's prestige.
The statement was released after Morsi met the ministers of defence and interior, head of the general intelligence, chief of staff of the armed forces, chief of operations of the armed forces and other army officials.
Morsi also said there would be no talks with "the criminals".
The kidnappers are demanding the release of fighters convicted last year of attacks that killed seven people, six of them members of the security forces.
A video posted online on Sunday showed seven blindfolded men with their hands bound above their heads, who said they were the hostages, begging Morsi to free political detainees in Sinai in exchange for their own release.
The video, which would be the first sign of the hostages since their kidnapping, could not be independently verified.
Al-Masry Al-Youm, an independent newspaper, reported that parents and friends of the seven men who appeared in the video had confirmed their identities.
In Monday's attack, fighters opened fire on the riot police facility in Al-Ahrash from a truck, security officials said.
Security forces shot back at the attackers, they said. There were no casualties.
In August last year, 16 Egyptian border guards were killed in an attack blamed on armed groups who then hijacked an armoured vehicle that they smashed across the border into Israel, where they were killed by Israeli forces.
Armed groups have expanded into a security vacuum in Sinai that the state has struggled to fill since Hosni Mubarak was swept from power in 2011.
The groups have attacked targets in North Sinai and launched raids into Israel.