Seven army personnel were killed and six others injured when their patrol was targeted by a remotely detonated roadside bomb southwest of Al-Arish on Sunday. The explosive device exploded as the patrol responsible for protecting the Egypt-Jordan natural gas pipeline, bombed 26 times in the last three years, passed by. “Such cowardly terrorist operations only increase the steadfastness of the Armed Forces and their determination to eradicate terrorism in Egypt,” said army spokesman Mohamed Samir. Militant attacks have claimed the lives of more than 500 security personnel since July 2013. Though Ansar Beit Al-Maqdis, which has been at the forefront of militant groups launching attacks against security targets since the ouster of President Mohamed Morsi in July 2013, has not claimed responsibility for the attack, security experts believe it is likely to be behind the operation. The explosion came days after the arrest of Ansar Beit Al-Maqdis commander Walid Waked Attallah, and after Adel Habara and six other Ansar Beit Al-Maqdis members had their death sentences for involvement in the killing of 25 conscripts in August 2013 referred to the Grand Mufti. A final verdict is expected on 6 December. Attallah, widely believed to be the head of Ansar Beit Al-Maqdis, was arrested in Rafah, say security sources. One of the most wanted militants in Sinai, Attallah is thought to be the mastermind behind scores of attacks targeting police and troops. “Ansar Beit Al-Maqdis is a large organisation and has the potential and capacity to recruit new cadres, though the detention of its leaders will compromise its ability to launch attacks,” says security expert Khaled Okasha. Ten days ago security forces reported that Shahtah Farhan, another leading member of Ansar Beit Al-Maqdis, had been killed during a raid in Rafah. Last week military forces in Sinai scored another success when a large cache of weapons earmarked for Ansar Beit Al-Maqdis was discovered. It is the largest consignment of arms yet to have been captured. Last Thursday in Al-Arish two policemen were killed and another wounded another when a rocket propelled grenade (RPG) hit their patrol car. “It's not that easy to fully secure Sinai, a vast area and many exposed roads. It is necessary for security forces to carry out pre-emptive operations in order to foil terrorist attacks,” says Okasha. A statement issued by the cabinet on Sunday expressed deep sorrow over the deaths of the seven soldiers and extended sympathy to their families. The statement continued by underlining the government's resolve “to uproot terrorism and provide security and stability for all citizens”. “Despite these latest terrorist attacks the security situation in Sinai is improving,” says security expert Sameh Seif Al-Yazal. In order to combat improvised explosive devices Al-Yazal urged the employment of more advanced equipment and a greater number of aircraft. Washington delivered ten long delayed Apache helicopters to Cairo. In October 2013 the US administration announced the suspension of part of its annual military aid to Egypt, including the 10 Apache aircraft, until Egypt made progress on democratisation. In April Washington lifted the ban on the delivery of the helicopters, citing the need to support anti-terrorism operations in Sinai. Security experts believe the US-made Apache helicopters will enhance the ongoing security campaign in the Sinai where attacks against security forces escalated following the 2013 ouster of Mohamed Morsi. On the same day as the Al-Arish RPG attack a bomb exploded in the Nile Delta city of Tanta injuring 11 people. The home-made bomb was detonated near Al-Sayed Al-Badawi Mosque as tens of thousands of people marked the last night of the moulid of the 13th century revered Sufi Sheikh. Two days earlier a primitive bomb planted in a car in Ramses Street was detonated in front of the Supreme Court building in downtown Cairo. The explosion injured 14. In a statement issued on Saturday the Interior Ministry said 52 people, from eight terrorist cells, has been arrested. They were found to be in possession of weapons, explosives and large sums of money. The cells, said the ministry, planned to target railways, public transport, and the electricity grid as well as plant bombs in crowded public spaces. Arrests were made in Giza, Minya, Daqahliya, Alexandria, Fayoum and Sharqiya.