At least 20 people were killed and 114 others injured tonight in an explosion at an exclusive club in northern Bogota. Security officials said early evidence suggested the blast was set off by a car bomb.

The powerful explosion cast the wealthy neighborhood around the Club El Nogal into a scene of grief and fear as ambulances, army troops and firefighters arrived to attend to the injured and stem rising panic in the streets.

Officials did not immediately assign blame for the explosion, but the country's largest guerrilla army has turned increasingly toward urban violence in recent months.

The blast occurred a little after 8 p.m. at the upscale sports and dinner club, frequented by Colombia's political and economic elite. The U.S. ambassador's residence is located behind the club.

Officials said the explosion likely came from inside the club's parking garage. Its force crumbled several of the building's 10 floors and set off a fire that burned late into the night.

"It was a huge explosion. I thought an airplane had crashed outside," Luis Moreno, who lives across the street from the club on Seventh Avenue in northern Bogota, told the Associated Press. The explosion blew out walls of two stories of the garage, raining rubble onto the street below.

Officials closed Seventh Avenue, a major route in the capital, as they brought in ambulances to whisk the injured to hospitals. Army troops arrived to secure the area, where authorities blocked cell phones from functioning in case one could be used to trigger another bomb during the rescue.

If the blast was the result of a bomb, it would be one of the deadliest bombings in the capital in recent times. Nineteen people were killed on Aug. 7, when Colombia's largest guerrilla army, the Revolutionary Armed Forces of Colombia (FARC), used mortars to attack the presidential palace during the inauguration of Alvaro Uribe.

Uribe was elected on a pledge to wage a broader war against the FARC, while the guerrillas have increasingly used urban terror tactics to shake the country's confidence in the popular president. The FARC, as well as a smaller guerrilla group known as the National Liberation Army and a large paramilitary force that fights against them, are considered terrorist organizations by the U.S. State Department.

Firefighters search the site of an explosion at the club in Bogota, Colombia's capital. Officials said the blast was likely set off in the club's parking garage.Police in Bogota escort injured patrons from the club, which was frequented by the political and economic elite.The explosion blew out part of the 10-story club's garage, where officials said it may have been detonated.