BINGHAMTON, N.Y. - The man who gunned down 13 people on Friday was well known at a Johnson City, N.Y., outdoors store, where he often purchased or exchanged handguns, a store employee said.Jiverly A. Wong, 41, frequently exchanged guns at the store, said Dave Henderson, Gander Mountain's outdoor education series coordinator. Wong would buy a handgun and shoot it for a few weeks before returning it, saying he didn't like the gun, Henderson said.

"He was in there real regular. Everybody knew him," Henderson said.

Police suspect Wong walked into the American Civic Association in Binghamton, N.Y., on Friday, killing 13 people and wounding four others before shooting himself. Police found two semiautomatic handguns and a satchel full of ammunition at the scene.

Broome County Sheriff David Harder said Wong last bought a handgun on March 17. He could not say whether that gun was one of the two used in the killing spree.

Harder also confirmed Wong had bought at least one gun at Gander Mountain. Harder has seen records of Wong's gun purchases because requests for pistol permits go through the sheriff's office.

Wong had two handguns registered to him on a gun permit he got in 1996 or 1997, police said.

Henderson, whose primary role at Gander Mountain is to teach and organize seminars, said he worked the gun counter when staffing at the store was low. In the 20 or so times he worked the gun counter in the past six months, Henderson said Wong either bought or exchanged guns five or six times.

Around Christmastime last year, Wong came back to the store the day after purchasing a gun, saying he had changed his mind and wanted to get a new one. He hadn't yet received the first gun, a process that takes about two weeks, Henderson said.

The guns used in the attack were a 9 mm and a weapon with an interchangeable barrel that could switch from 9 mm handgun to .45-caliber.

Wong bought a .45-caliber handgun within the past month and a half at Gander Mountain in Johnson City, Henderson said. Each time he bought or exchanged a weapon, Wong had to pass an FBI background check.

Henderson writes a column about outdoors issues twice a week for the (Binghamton, N.Y.) Press & Sun-Bulletin.

Language obstacles

Wong also frequently grew agitated when store employees couldn't understand his English, Henderson said. A couple of times, Henderson had to pass Wong off to another store employee because Wong would get annoyed.

"He would get frustrated," Henderson said in a telephone interview from Madison, Wis., where he was attending a gun show. "There were times I wouldn't even talk to him anymore."

Friends and family have told police Wong often felt humiliated and picked on because he didn't speak English well. He was taking English classes at the American Civic Association until he dropped out in the first week of March, Binghamton Police Chief Joseph Zikuski said.

Henderson said he remembered Wong because of his distinctive first name and his regular appearances at the store.

During one visit, Wong told Henderson that he had changed his name from Voong because "Americans can't pronounce my real name."

Police have said Wong at some point changed his name.

Upon landing in Wisconsin on Friday night, Henderson saw news reports about the massacre in Binghamton. When Wong's name was released, he recognized the first name instantly, he said, but the last name was slightly different than Wong's driver's license and gun permit.

He said he called the manager of the store, who checked the records and confirmed Wong bought guns at Gander Mountain.