12 killed in Tripoli explosion, source says

BEIRUT, Lebanon (CNN) -- An explosion targeting a bus rocked a business district in central Tripoli Wednesday morning, killing at least 12 people and wounding 50 others, a senior member of Lebanon's internal security forces told CNN.

Among the dead were at least nine Lebanese soldiers, the source said.

The attack happened at about 8 a.m. along Masarif Street in the Lebanese port city located about 40 miles northeast of Beirut. The blast came from outside the vehicle, but it was uncertain whether it came from a roadside bomb or a car bomb.

The civilian bus contained mainly military personnel, the source said. The wounded included bystanders who were not on the bus.

The attack came hours ahead of a landmark visit by President Michel Suleiman to neighboring Syria -- the first visit by a Lebanese president to Damascus in about three years.

Suleiman's meeting with Syrian President Bashar al-Assad resulted in an agreement to establish diplomatic relations between the two Arab nations.

The United Nations Security Council labeled the attack an act of terrorism Wednesday.

"Members of the Security Council condemned, in the strongest terms, the terrorist attack in the Lebanese town of Tripoli," a U.N. statement said. "We need to bring the perpetrators, organizers, financiers and sponsors of this reprehensible act of terrorism to justice."

CNN's Nada Husseini and journalist Anthony Mills contributed to this story.

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