A GUNMAN OPENED fire in a classroom building at a US Naval Air Station in an attack that left four people dead, including the shooter, and multiple people wounded.

The shooting in Pensacola, Florida, the second at a US Navy base this week, prompted a massive law enforcement response and a lockdown at the base.

Up to eleven people were shot all together, including two sheriff’s deputies who were the first to respond, one of whom killed the gunman, Escambia County Sheriff David Morgan said.

One of the deputies was shot in the arm and the other in the knee, and both were expected to recover, he said. The number of wounded has not yet been confirmed by the US Navy. 

Morgan would not say if the gunman belonged to the military and said he did not want to speculate on whether the shooting was terrorism-related.

US media reports have said the gunman was a member of the Saudi military who was training at the facility. 

Police received their first call about the shooting shortly before 7 am (12pm Irish time), Morgan said. 

The base remained closed until further notice and those still on base would remain there until it was safe to evacuate, said commanding officer Captain Timothy Kinsella Jr.

NAS Pensacola employs more than 16,000 military and 7,400 civilian personnel, according to its website.

One of the Navy’s most historic and storied bases, it sprawls along the waterfront southwest of downtown Pensacola and dominates the economy of the surrounding area.

It is home to the Blue Angels flight demonstration team, and includes the National Naval Aviation Museum, a popular regional tourist attraction.

Escambia County Commissioner Jeff Bergosh, who works at the Naval Air Station as a civilian contractor, told the Pensacola News Journal he was in a queue to go through the gate when it was shut down due to the active gunman report.

The shooting is the second at a US naval base this week.

A sailor whose submarine was docked at Pearl Harbour, Hawaii, opened fire on three civilian employees, killing two before taking his own life.

US President Donald Trump tweeted to say the situation is continuing to be monitored as the investigation continues. 

US vice president Mike Pence tweeted: “Saddened to hear of the horrible shooting at Naval Air Station Pensacola & continuing to monitor the situation.

“Praying for the victims & their families & we commend the first responders for their swift action in taking down the shooter & getting those on base to safety.”

With reporting by AFP