Egyptian troops shot dead an Islamist terrorist described as a leader of the Sinai group that claimed a failed attempt on the life of the interior minister and the murder of a high-level security official, the military said on Monday.Attacks on soldiers and policemen in Sinai have become commonplace since the army ousted Islamist President Mohamed Morsi in July in the face of mass unrest over his rule.The Egyptian army said Ibrahim Abou Eita was killed in an exchange of gunfire with soldiers near the town of Sheikh Zuweid in Sinai and it described him as a leader of the Islamist terrorist group Ansar Bayt al-Maqdis.The army referred to Abou Eita, also known as Abou Suheib, in a statement on Facebook as “one of the most dangerous” terrorists in North Sinai, who had been sought for attacks on security forces in the region.Ansar Bayt al-Maqdis had claimed responsibility for killing an official who security sources say had been due to testify in one of several legal cases against Morsi, and for a bid to kill Interior Minister Mohamed Ibrahim with a car bomb in September.Security officials have been assessing the threat posed by Ansar Bayt al-Maqdis, which is said to have 700 to 1,000 members. It is considered to be the second-largest Islamist militant group in Sinai behind Salafiya Jihadiya, which has an estimated following of around 5,000 members.Ansar Bayt al-Maqdis, whose name means “Supporters of Jerusalem”, has claimed rocket attacks launched on Israel from Sinai and at least 10 attacks in the past two years on a gas pipeline linking Egypt, Israel and Jordan.On Sunday, army spokesman Ahmed Muhammad Ali said that the Egyptian army had found two vehicles rigged with explosives in North Sinai intended for suicide bomb attacks. Security forces shot at one vehicle, causing it to explode before reaching a security base in Sheikh Zuweid, the Egyptian State Information Service website reported.DNA samples are being taken from the remains of the suicide bombers in order to identify them.A second bombing attempt was thwarted when a car with no license plates was detected and when the security forces shot at the car it exploded.Separately, an Egyptian court sentenced three Morsi supporters to life imprisonment, judicial sources said on Monday, in the latest tough ruling against opponents of the army-backed interim government.The court in Qalyubia province, near Cairo, sent the three men to jail for 25 years for attacking security forces, terrorizing citizens, possessing firearms and damaging public and private property during a pro-Morsi protest.The sentence coincided with the first court appearance of Muslim Brotherhood leader Mohamed Badie for inciting violence since he was arrested in a state crackdown on the group.It came days after a court decided to release fourteen Islamist women jailed for 11 years after they demonstrated in support of Morsi, slashing their sentences in a case that had outraged opposition groups and human rights campaigners. Security forces dispersed camps set up by protesters demanding Morsi’s reinstatement on August 14, killing hundreds. Most of the Brotherhood’s leadership has been arrested since the army overthrew Morsi in July following mass protests against his rule.Morsi’s Muslim Brotherhood was banned by a Cairo court in September. Morsi is himself standing trial on charges of inciting the killing of protesters during violence outside the presidential palace a year ago.