PENSACOLA, Fla. — All employees at the Naval Air Station Pensacola were allowed to return to work on Monday just days after the deadly mass shooting where three sailors were killed.

• FBI still seeking to confirm motive behind shooting
• Shooting is being investigated as act of terrorism
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Visitors with a current Department of Defense card were also allowed back on base.

Investigators have identified the shooter as 21-year-old visiting Saudi Air Force officer Mohammeed Alshamrani, who killed three people and wounded eight.

Using a Glock 9 mm that he bought legally in Florida, Alshamrani wounded two Escambia County Sheriff's Office deputies, one in the arm and one in the knee, before one of them killed him. Both deputies are expected to survive.

The three people who were killed are: Airman Mohammed Haitham, 19, ensign Joshua Watson, 23, and airman apprentice Cameron Walters, 21.

Gov. Ron DeSantis is now calling for stricter checks on who is allowed on bases.

"You know, you have foreign military personnel coming to our base, they should not be doing that if they hate our country," said DeSantis.

The FBI confirmed they are still working to identify a motive, but are now investigating this as an act of terrorism. It also has been categorized as a mass shooting, as described by the FBI.

"This allows us to take advantage of investigative techniques that can help us more quickly identify and then eliminate any additional potential threats to the rest of our community," said Rachel Rojas, FBI Special Agent in charge of the Jacksonville division.

According to the New York Times​, documents revealed that the Saudi trainee filed a formal complaint after an instructor referred to him as "Porn Stash" in front of several other students, an apparent reference to the way he wore is mustache. In that complaint, he wrote that he was furious. 

Authorities believe the gunman made social media posts criticizing the U.S. under a user handle similar to his name, but federal law enforcement officials are investigating whether he authored the words or just posted them, said the official, who was not authorized to discuss the matter publicly and spoke to The Associated Press on condition of anonymity.

U.S. officials confirm all witnesses are now being questioned, including some Saudi nationals. 

The Associated Press contributed to this story.