At around 10 a.m., police responded to an aggravated assault call in the 2100 block of Avenue P.
Deputies said that EMS were treating a tree trimmer who had been injured by a man carrying a knife.
At the scene, authorities said the knife-wielding suspect remained on the scene, threatening emergency personnel and leading to two Galveston officers opening fire.
Officials said the injured suspect was carried by ground ambulance to the trauma center at UTMB Health's John Sealy Hospital, where he passed away.
At this time, the suspect's identity has not been released.