An Egyptian court yesterday sentenced 14 militant Islamists to death by hanging and four to life imprisonment for attacks on army and police forces in the Sinai Peninsula last year.

The verdicts showed the state's determination to deal firmly with militant activity in Sinai, which has increased since the overthrow of President Hosni Mubarak in February 2011.

Security forces are mounting operations in the area following the killing of 16 Egyptian border guards in August.

The men, members of a militant group called Tawhid wa al Jihad, were charged by the prosecutor with killing three police officers, an army officer and a civilian in attacks carried out in June and July, 2011.

Eight of the 14 death sentences were in absentia, court sources said.

"This court decision is a milestone. It gives a strong message to militant groups that President Mohamed Mursi's government will not tolerate attacks on the Egyptian armed forces and police," said Nageh Ibrahim, an Islamist researcher and a former militant.

The verdicts were met with cries from the accused against Mr Mursi, the Islamist head of state elected this year and who the defendants blamed for the court's decision. One defendant shouted: "Mursi is an infidel and those who follow him are infidels."

Others cried "God is great" as they listened to the judge from inside the metal cage in which they stood during trial sessions.

The bearded men in the cage wore traditional white robes and some were seen holding the Koran. They were accused of opening fire on a police station and a bank in the city of Arish in northern Sinai.

The prosecutor said the Tawhid wa al Jihad group was propagating a hardline Islamist view that allows adherents to declare the head of state an infidel and to carry arms against the government.

The same group was accused of carrying out a series of bomb attacks in 2004 and 2005 against tourist resorts in south Sinai, which lead to the deaths of 34 people.

Egypt and Israel have said they are co-ordinating on the security operation in Sinai in which hundreds of Egyptian troops with tanks, armoured vehicles and helicopters were sent in a joint operation with police to raid militant hideouts, arrest suspects and seize weapons.

Mr Ibrahim, who was jailed during the 1990s but later became one of the leading Islamists to call for an end to violence against the state, said the verdicts will deter other militants from attacking their neighbour Israel.

"Mr Mursi's government is adamant about stemming any attacks across the border because this will give Israel an incentive to reoccupy Sinai. Now is the time for development, not war," Mr Ibrahim said.