Peter Aguon Maguadog was armed with two handguns Monday as he made his way through the Seventh Day Adventist Clinic, where his wife worked and where he was once employed, police spokesman Officer A.J. Balajadia said.
The couple had been going through divorce proceedings, Balajadia said.
Maguadog's wife, whose name wasn't available, and another woman were pronounced dead at Guam Memorial Hospital, where he died while undergoing surgery, officials said.
The four other victims were in stable condition, Balajadia said.
Five of the victims were shot on the second floor of the two-story building, while the sixth, a man who had been taken hostage, and Maguadog were shot on the first floor, he said.
"I've seen shootings, but I've never seen anything like this on Guam," said Balajadia, an 18-year veteran of the force.
More than 100 people were in the building when the gunfire erupted, police said.
Besides his wife, it appeared Maguadog fired at random, rather than singling out victims to shoot, Balajadia said.
The shooting began about 11:30 a.m. and ended about 30 minutes later, he said.
Guam, with a population of 152,000, is a U.S. territory, located west of the international date line, about 3,800 miles west of Hawaii.
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