Washington ? Freed from a judge’s gag order, FBI officials and Las Vegas police confirmed Tuesday night they learned in the fall of 2002 about two videotapes suggesting terrorists had cased the city’s casinos but decided it wasn’t necessary to alert the public.

The officials also strongly disputed they didn’t take the evidence seriously, as suggested in Justice Department documents obtained by The Associated Press and by a federal prosecutor in Detroit who alerted them to the evidence.

The tapes were shown to casinos in the fall of 2002, officials said, but they added there was differing recollections about whether some local officials declined a later opportunity to learn more about the surveillance from an FBI agent from Detroit who had worked on the case.

“We took the tapes seriously,” Special Agent David Nanz in Las Vegas said in an interview. “When we get a tape like that, … further investigation is required to determine its relevance. And that’s what we did.”

In documents and interviews reported by the AP on Monday, authorities in Detroit alleged as early as September 2002 that Las Vegas authorities didn’t want to issue a public warning because of concerns it might hurt tourism or affect the casinos’ legal liability.

Las Vegas authorities denied Tuesday those factors affected their decision.

Nanz said one of the two tapes, the Spanish al-Qaida footage, was still classified at the time and Las Vegas authorities weren’t immediately told that a witness, named Youseff Hmimssa, would corroborate the threat on the Detroit tape by saying members of a terror cell in Detroit had vowed to destroy the tourist city.

“The FBI in Las Vegas was not made aware in advance that Hmimssa’s testimony would implicate security issues with Las Vegas,” he said.