A car packed with at least 110 pounds (50 kilograms) of explosives blew up in an office district of Colombia's capital Thursday, shattering windows and injuring nine people, police said. No deaths were reported.
The blast occurred at 5:30 a.m. (1030 GMT) outside a 12-story building housing Caracol Radio, the Spanish news agency EFE and the Ecuadorean consulate, as well as the offices of several banks and politicians, including former President Cesar Gaviria.
Investigators were not sure of the target or who was behind the bombing, said Hermes Ardila, chief of prosecutors in a special anti-terrorism unit. He said by telephone eight hours after the bombing that investigators had not linked the attack to any particular armed group.
President Juan Manuel Santos hurried to the scene and called the explosion "a terrorist act," saying it was meant to sow fear and create skepticism about the government.
"We are going to continue fighting terrorism with everything we have," said Santos, who took office on Saturday. He replaced Alvaro Uribe, whose tough tactics sharply weakened the leftist guerrilla groups that have fought the government for decades.
Santos toured the blast site surrounded by security agents and urged Colombians to go on with normal activities.
Bogota's health secretary, Hector Zambrano, said at least nine people were injured. Most were treated for cuts and released, but three people remained under care, he said.
Pinzon said most of those hurt had been on a bus that was passing by as the bomb exploded.
Authorities said no arrests had been made.
The national police operations director, Gen. Orlando Paez, said the car was packed with at least 110 pounds (50 kilograms) of explosives and the blast shattered windows in at least 30 buildings, smashed the facade of a bank and left scraps of the destroyed car scattered in the street.
Gen. Cesar Pinzon, the city's police chief, said authorities had located the owner of the car that exploded. Pinzon said it had been reported stolen July 31 from a shopping center in the north of the city.
The director of the private Conflict Analysis Resource Center, Jorge Restrepo, said the fact the bomb went off before rush hour and used a relatively small amount of explosive showed it was meant as a political message. He called it "a very early greeting" to Santos' government from armed groups.
The explosion "is an example that they still have the ability to execute this type of terrorist action," Restrepo said.
A car bomb that exploded in March in the Pacific coast city of Buenaventura killed at least nine people and injured about 50. Bogota had not suffered a car bombing since January 2009, when a blast at an automatic teller machine killed two people.
Caracol Radio continued broadcasting despite the blast. None of the 12 people who work at the station at that hour were injured, said Ricardo Alarcon, manager of Caracol. He said it wasn't clear Caracol was the target of the attack.
EFE's director for Colombia, Esther Rebollo, said its offices were not damaged.
Governments across Latin America from Mexico to Argentina condemned the bombing, as did the Union of South American Nations.
Venezuelan President Hugo Chavez's government denounced the bombing, calling it a "terrorist act against the sister nation of Colombia and against its fervent desire to live in peace."