EL-ARISH, Egypt (AP) -- An Egyptian militant group claimed responsibility Sunday for twin suicide bombings that targeted a military checkpoint and a tourist bus, killing at least one soldier and wounding nine in southern Sinai.
In a statement posted on militant websites, the al-Qaida-inspired group Champions of Jerusalem told the Egyptian army: "We will not rest until we achieve retribution for the blood and honor of the Muslims."
The group has been behind the deadliest attacks against military and police installations in Egypt following the military overthrow of Islamist President Mohammed Morsi last year. Another new group, known as Egypt's Soldiers has claimed responsibility for several smaller bombings targeting individual officers.
Security officials fear the attacks on troops will intensify ahead of presidential elections scheduled for later this month. Retired Field Marshal Abdel-Fattah el-Sissi, the former military chief who oversaw Morsi's ouster, is the front-runner.
In a boost to el-Sissi, the ultraconservative Islamist Al-Nour party publicly endorsed him for presidency. In a statement published Sunday, the Salafi party said after meeting with el-Sissi and his opponent, leftist Hamdeen Sabahi, it decided to support the former military chief.
"He has a strategic vision that qualifies him to run the country. Things will work under him," Younis Makhyoun, the party leader, told private television station CBC. "He has no intention to exclude anybody."
Al-Nour party, formerly allied with Morsi's Muslim Brotherhood, came in second with nearly a quarter of the parliament seats in the 2011-2012 parliamentary elections. It later fell out with the Brotherhood, complaining that it was monopolizing power.
It was not clear if al-Nour can galvanize Islamists to support the former army chief. The party supported the military overthrow of Morsi, a move that has cost it support.
The Salafi movement is new to the political scene in Egypt. It previously shunned politics and holds an even more conservative and strict interpretation in Islam than the Brotherhood.
Friday witnessed a series of attacks in Cairo and southern Sinai, a tourist destination that has seen four suicide bombings since Morsi's ouster, including one in February that killed three South Korean tourists. On Friday, a bomber blew himself up near a tourist bus carrying Egyptian workers in el-Tor, in southern Sinai, killing only himself and wounding four, security officials said. The Health Ministry initially said a civilian was killed.
It was not clear if the bomber was aiming to target foreign tourists or the Egyptian workers.
On the same day, another attacker blew himself up at an army checkpoint in el-Tor, killing a soldier and himself, and wounding five others, the officials said. Initially, a civilian also was believed to have been killed in the attack. In Cairo, a homemade bomb planted at a police post killed an officer, while a car used usually by military officers exploded, killing a civilian. No one claimed responsibility for these two attacks.
Also Sunday, security officials said masked gunmen killed a retired intelligence officer in el-Arish, the capital of northern Sinai, after he dropped his children at school. The retired officer was heading a local prominent charity organization, and the motive for his killing was not immediately clear.
The security officials spoke on condition of anonymity because they were not authorized to speak to journalists.
Associated Press writer Maamoun Youssef in Cairo contributed to this report.
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