"We have been asked to help with analyzing the video tapes from the surveillance cameras, that's true," Tracy Jacobson, spokeswoman for the American Embassy, said.
So far there are no FBI agents in Latvia working on the case.
"We have not brought any agents here," Jacobson said. "The tapes would be sent to Washington for the analyses."
The FBI bureau in Tallinn had little to say. Legal attaché William Moschella wouldn't comment.
Krists Leiskalns, spokesman for the state police, said police are still analyzing the material filmed by the surveillance cameras in the shopping center.
"Only about 10 percent of the video cameras are useful for the investigation," Leiskalns said.
Leiskalns said that FBI has been contacted because they have better technical equipment to work on the tapes.
"There are no FBI agents in Latvia. They are working from the [United] States," Leiskalns said.
There have been contradictory statements regarding the quality of the film provided by Centrs' cameras. According to an anonymous source who spoke to LETA, it is only possible to see silhouettes of people without any features.
Those statements have been denied by Guntis Uzulins, vice president of the security firm Group 4 Securitas Latvia, which is responsible for security in Centrs, who said that the quality of the films is good enough.
Uzulins told LETA that the primary task of the cameras was to record thefts at the store.
According to Uzulins, photographs were scanned from the video records to be used by the police for their compiled pictures of possible witnesses and suspects for the investigation.
Four people resembling the police pictures have already been stopped by border guards for questioning. All of them were quickly released.