Cairo, Aug 20 (IANS): Egypt continued to simmer with tension Tuesday even as 11 people were arrested in connection with attacks on security forces and the Muslim Brotherhood named a temporary new leader.

The Egyptian armed forces Tuesday arrested the 11 people, including two Palestinians, in the Sinai over attacks on the police and army premises.

The forces raided several criminal hideouts early Tuesday morning and arrested them, Xinhua reported citing the official Egyptian news agency MENA.

The operation came one day after suspected militants ambushed two buses carrying security forces in Egypt's northern Sinai, killing at least 25 soldiers.

The buses were Monday carrying the policemen from their base in Rafah city to their homes for vacation, when the militants fired rocket-propelled grenades at the vehicles.

The security condition deteriorated in Sinai since the ouster of former president Hosni Mubarak in 2011, and became worse after his successor Mohamed Morsi's government was toppled, which triggered violence between security forces and Morsi's supporters.

Meanwhile, the Muslim Brotherhood Tuesday appointed Mahmoud Ezzat as its temporary new leader, after its general guide Mohamed Badie was arrested.

A statement on the Muslim Brotherhood's Freedom and Justice Party website named Ezzat, deputy of the former general guide, as the new chief as per the group's internal regulations, Xinhua reported citing MENA.

“In the absence of the general guide either for travelling abroad, or for being sick or in emergency cases, his deputy is entitled with his responsibilities,” the statement said.

Badie was arrested early Tuesday in an apartment in Tayran street in Nasr City district of Cairo and then transferred with intensive security measures to Torah prison, where former president Hosni Mubarak and his two sons are detained

Two other leading members of the Brotherhood - Youssef Talaat and Hassan Maleik - were also arrested along with Badie.

On July 4, just a day after the ouster of Islamist president Mohamed Morsi, acting prosecutor general Ahmed Ezz el-Din had ordered an arrest warrant against the Brotherhood's top leader on charges of inciting the killing of anti-Morsi protestors.