Gray smoke could be seen billowing near the Mediterranean coast, but the source of the explosion was not immediately known.

The security official, speaking on condition of anonymity in line with military rules, told The Associated Press there was an explosion in the predominantly Christian Dora-Karantina neighborhood. He gave no further details.

A Lebanese Broadcasting Corporation correspondent who happened to be in the area reported seeing the charred body of at least one person killed in the blast. The station also reported a person wounded in a car belonging to the American Embassy.

Television footage showed several damaged cars, including an SUV with tinted windows, similar to those used by U.S. diplomats.