The brother of a 23-year-old member of the U.S. Navy who was fatally shot when a member of the Saudi Air Force opened fire at the Pensacola Naval Base on Friday has posted an emotional tribute on Facebook, saying his loved one “saved countless lives.”

Joshua Kaleb Watson was shot several times by a Saudi national, identified by multiple news outlets as Mohammed Saeed Alshamrani, who was training at the facility, but managed to escape the carnage and alert first responders so the assailant could be neutralized, his family said.

“Today has been the worst day of my life,” Adam Watson wrote on Facebook. “My youngest brother gave his life for his country in a senseless shooting. Joshua Kaleb Watson saved countless lives today with his own. After being shot multiple times he made it outside and told the first response team where the shooter was and those details were invaluable.”

Watson was one of three people who were fatally injured when Alshamrani opened fire in Building 633, which is part of the Naval Aviation Schools Command, and carried out the shooting over two floors of the training area.

He was taken to a local hospital but later died of his injuries, according to WDHN news, which reports that the victim graduated from Enterprise High School in Pensacola in 2014 and was part of the National Honor Society and the French National Honor Society.

He then went on to train at the U.S. Naval Academy where he was on both the commandant’s honors list and the dean’s list for his academic acumen. He trained as part of the Navy’s rifle team and his family says it was his lifelong dream to serve his country.

“He died a hero and we are beyond proud but there is a [hole] in our hearts that can never be filled,” the Facebook tribute says. “When we were little I gave Kaleb the name little poot and it stuck. It eventually evolved into pootis and finally uncle poot.”

The grieving brother then goes on to deliver a hear wrenching farewell. “Just wish I could talk to him one more time or wrestle with him one more time even though he could probably take me now,” he writes. “Thanks for all the thoughts and prayers in this difficult time.”