EL-ARISH, Egypt - A suicide bomber on Wednesday rammed his explosives-laden car into the military intelligence headquarters in a border town in Egypt's volatile Sinai, killing at least three soldiers and wounding 20 people, security officials said.
The attack in the town of Rafah nudged the violence in the strategic Sinai Peninsula closer to a full-blown insurgency, compounding Egypt's woes at a time when the country is struggling to regain political stability and economic viability more than two years since longtime autocrat Hosni Mubarak was toppled in a popular uprising.
Wednesday's bomber drove into the one-story building at high speed, collapsing the entire building and burying an unspecified number of troops under the rubble, two security officials said, speaking on condition of anonymity because they were not authorized to speak to the media.
At least twelve soldiers and eight civilians were wounded in the bombing.
Simultaneously, militants fired rocket propelled grenades at an army checkpoint not far from the military intelligence building, the officials added.
Militants in Sinai, some with links to al-Qaida, have been targeting for months Egyptian forces in the strategic peninsula bordering Gaza and Israel. Their attacks have become much more frequent and deadlier since the ouster this summer of Mohammed Morsi, Egypt's Islamist president. After Mubarak's ouster, Morsi became the country's first democratically elected president in 2012 but he was deposed in July by the military after days of massive street protests against him.
Earlier this week, the Egyptian military launched a major offensive against the militants in the northern region of Sinai.
Officials have described the offensive, which started on Saturday, as the biggest sweep of the area in recent years, aiming to weed out al-Qaida-inspired groups that have taken control of villages in northern Sinai.
Five days of military operations so far have left 29 Islamic militants dead and the military has boasted of capturing weapons caches, missile launchers, and dozens of vehicles and fuel storage sites. Some 30 militants were arrested during raids - mostly low-level operatives.
One officer and two soldiers have also been killed in the operation since Saturday.
On Monday, Egypt's state news agency MENA cited unnamed senior security officials as saying at least six militant groups with an estimated 5,000 members operate in Sinai. The militants use mountains in north and central Sinai as hideouts, where the rugged terrain is difficult to search.
But the repeated security operations have increased tension with local residents, who accuse authorities of randomly targeting homes and arresting innocent people.