Updated

A booby-trapped car exploded at a barracks housing coast guard officials in Algeria on Saturday, killing at least 28 people and injuring about 30, the country's official news agency reported, citing hospital authorities.

Al-Qaeda's North African Wing says it is behind the Algerian suicide attacks, according to Al-Jazeera Television. It said al Qaeda Organisation in the Islamic Maghreb said in an Internet statement it was behind both Saturday's bombings, and the attacks in the town of Batna less than 48 hours earlier. The television station gave no further details

Today's explosion ripped through the northern coastal town of Dellys, about 50 kilometers (30 miles) from Algiers, shattering many of the town's windows. In the confusion, security authorities initially gave a lower death toll before the APS agency released an official count by hospitals. Some of those injured were in serious condition.

A recent spate of major bombings in Algeria has generated fears of a return to the mass-scale violence of the 1990s, when Algeria's Islamic insurgency peaked. The country, a staunch U.S. ally in the war against terror, has been trying to turn the page on the 15-year insurgency that killed 200,000 people. Until recently, its efforts appeared mostly successful.

The attack came just two days after another bombing killed at least 22 in a crowd of people in eastern Algeria who were waiting to see visiting President Abdelaziz Bouteflika, who has devoted his eight years in office to ending the insurgency.

There was widespread speculation that Bouteflika was the intended target of that attack, though Algerian officials kept silent on the question. Police said the bomber was killed by security services after he dropped the explosives and tried to escape.

There was no immediate claim of responsibility in either attack. However, an Al Qaeda affiliate calling itself Al Qaeda in Islamic North Africa has been active in Algeria lately. On Friday, Interior Minister Noureddine Yazid Zerhouni warned terrorists that they have "one choice: turn themselves in, or die."

Algeria's insurgency broke out in 1992, after the army canceled legislative elections that a now-banned Islamic fundamentalist party was poised to win.

Widespread killing was on the wane until recently, but violence resurfaced this year after Algeria's Salafist Group for Call and Combat, or GSPC, officially linked with Al Qaeda, taking the name Al Qaeda in Islamic North Africa.

The group claimed responsibility for other attacks this year, including an April suicide bombing outside the prime minister's office in Algiers and a simultaneous attack on a police station that killed 32 people.

Al Qaeda's Algerian branch also said it was responsible for another attack in July, when a suicide bomber blew up a refrigerated truck inside a military encampment southeast of the Algerian capital, killing 10 soldiers.