Six Saudi nationals were reportedly detained for questioning after a Saudi Arabian aviation student killed three people and injured eight when he opened fire at the Pensacola Naval Base on Friday. The New York Times reports that while they believe the shooter acted alone, at least some of the Saudi nationals called in for questioning were seen filming the entire shooting. No one has confirmed if any of them were involved. SITE Intelligence, a group that monitors jihadist activity, also reported that a man with the gunman’s name, which was identified by the Times as Mohammed Saeed Slshamrani, posted a Twitter message hours before the shooting in which he referred to the U.S. as a “nation of evil” for its support of Israel.

Saudi Vice Minister of Defense Khalid bin Salman wrote on Twitter that many military personnel, including himself, trained in the U.S. “Like many other Saudi military personnel, I was trained in a U.S. military base,” he wrote. “And we used that valuable training to fight side by side with our American allies against terrorism and other threats.” The FBI are leading the investigation but have not confirmed whether it is terrorism-related.