The worse bomb, in the Belcourt district of Algiers, killed 17 and injured 52. It was outside a building that houses the Algerian newspaper Le Soir d'Algerie and the offices of several independent journalists and photographers. Witnesses said it blew a crater in the ground.
It was not immediately known whether any journalists were among the victims. Islamic radicals began targeting journalists in May 1993, and 58 have been killed, most recently an Algerian newspaper editor shot dead on Saturday.
Earlier yesterday, a car bomb planted in another quarter of the capital, Bab el Oued, wounded 41 people. No one immediately claimed responsibility for either attack, but suspicion fell on Islamic radicals trying to topple the military-backed government and replace it with strict Islamic rule.
The government, reacting to the widening violence, clamped down by ordering Algerian newspapers to submit their reports on terrorism to a government censor.
The bomb that wounded 41 exploded in front of a heavily protected city office, and the building was badly damaged. A hospital source said seven of the wounded were gravely injured.
A source said that the bombing may have been the work of the Armed Islamic Group, the most extreme of Algeria's militant factions. The source said a suspected group commando had been seen in the area. There were no other details, and the government did not confirm the report.