Official: 2 suspects in Tunisia museum attack got weapons training in Libya

(CNN) Two extremists who attacked a museum in Tunisia, killing 23 people, got weapons training at camps in Libya, an official said Friday. Most of the victims of Wednesday’s attack at the Bardo Museum in Tunis were foreigners.

The suspects were activated from sleeper cells in Tunisia, Security Minister Rafik Chelly said. He did not say who activated them. Tunisia’s security forces are working to break up other cells, but more investigations are needed.

“We know they can launch operations, but we must piece together clues in order to conduct an arrest,” Chelly said.

The minister’s revelation came as the nation marked 59 years of independence from France.

In an audio message posted online Thursday, terror group ISIS claimed responsibility for the attack. It identified two men and applauded them for killing and wounding “crusaders and apostates” with “automatic weapons and hand grenades.” And that bloodshed is “just the start,” the ISIS message warned.

CNN cannot independently verify the legitimacy of the audio statement. 

Authorities have arrested nine people in connection with the attack, including four directly linked to the bloodshed, according to a statement from Essebsi.