Gunmen killed two Egyptian policemen Wednesday in the Sinai Peninsula, the interior ministry said, in an attack claimed by Islamic State group jihadists.

Egypt's security forces have come under regular attack since the military ousted Islamist president Mohamed Morsi two years ago.

A bomb struck a bus carrying Egyptian policemen Monday, killing three and wounding 33, officials said, in the latest attack against security forces who are being targeted by jihadists.

The attack occurred in the Nile Delta province of Baheira, 260 kilometers (160 miles) north of Cairo, while the policemen were traveling on a civilian bus to work.

Egypt's Muslim Brotherhood leader Mohamed Badie, who has been sentenced to death, was handed another life term in prison Saturday for an attack on a police station.

A criminal court sentenced Badie, the Islamist movement's spiritual leader, over the attack in the northeastern city of Port Said on August 16, 2013.

Gunmen have seized four members of the Palestinian Islamic group Hamas from a bus bound for Cairo from the Gaza Strip, an Egyptian security official said on Thursday.

The identity of gunmen, who stopped the bus close to the Rafah border crossing with Gaza on Wednesday night, was not immediately clear.

Gunmen in Egypt boarded a bus carrying Palestinians from Cairo to Gaza and seized four of the passengers before letting the others continue, Hamas officials in the strip said early Thursday.

Interior ministry spokesman Iyad Bezem said in a statement that the kidnapping took place late Wednesday night in the troubled northern Sinai region as the bus headed for the Rafah border crossing into Gaza.

A powerful car bomb blast tore through a Cairo police building Thursday injuring at least 29 people in the latest attack claimed by the Islamic State group against Egyptian security forces.

Six policemen were among those wounded in the explosion but officials said none of the injuries were life-threatening.

The United States denounced Egypt's newly expanded counterterrorism law Tuesday, expressing concern about its potential impact on human rights in the country, a military ally of the U.S.

President Abdel Fattah al-Sisi signed a law Sunday that would expand the government's surveillance powers and, according to critics, muzzle dissent and target critics.

An official of the Palestinian Islamist movement Hamas has been detained at Cairo airport as he tried to enter Egypt, an airport source said Tuesday.

Hassan al-Saifi, whose name figures on an Egyptian watch list, was detained on arrival Monday, the source said, adding he was still at the airport and would likely be deported.

Leading Muslim clerics meeting in Cairo on Tuesday called for moderation in issuing religious edicts, in an attempt to counter extremist fatwas that sanction jihadist atrocities.

The muftis -- often chief interpreters of Islamic law in their countries -- and clerics agreed at the conclusion of the two-day conference on training for Muslim scholars and coordination on issues of Islamic law.

Top Muslim clerics gathered in Egypt on Monday to address extremist religious edicts in the face of an unprecedented threat from Islamic State group jihadists who have declared a "caliphate."

The muftis -- usually the official interpreters of Islam in their countries -- are meeting alongside other clerics over two days in Cairo to cope with what the clerics described as a rash of extremist fatwas, or edicts.