Authorities blamed Colombia's largest rebel group for a car bomb that exploded in the parking lot of a military university in Bogota and injured at least 18 people and may have targeted the army's top commander.
"I imagine this has to be the FARC. I don't see any other alternative," said Defense Minister Juan Manuel Santos, referring to the Revolutionary Armed Forces of Colombia, shortly after visiting the scene of the bombing.
The blast occurred just as the morning rush hour was ending at Nueva Granada military university, which was hosting an event attended by foreign dignitaries and the army's top general, Gen. Mario Montoya. Initial reports said none of them were injured.
Juan Pablo Corlazzoli, the representative for the United Nations' high commissioner for human rights in Colombia, was attending the conference on human rights in Colombia's armed forces at the time of the blast.
"The moment that conference began, the blast occurred from this vehicle a few meters from the conference room," said Corlazzoli. "Everyone was very calm, there were no scenes of panic, but there was concern."
Santos said the bomb had been placed in a Ford Explorer that passed through security in entering the school's parking lot.
"This looks like an unforgivable security lapse," said Santos.
All the windows of the building looking out on parking lot were blown out.
The attack may have been aimed at Montoya as the blast destroyed one of his armored cars, along with four other vehicles parked nearby.
Among those being treated in hospitals were 12 soldiers and bodyguards and 6 students. One was seriously injured and in surgery, said Nora Rodriguez, director of the military hospital.
Santos called the blast "a typical act of terrorism ... They are investigating what type of explosive was used."
He offered a reward of US$90,000 for information on those responsible.
The blast snarled traffic in much of northern Bogota, as roads were closed down and ambulances and anti-explosive vans raced through the streets.
Colombia is in a five-decade-old civil war that pits leftist rebels against the central government and far-right illegal militias.