MADISON, Wis. – A Green Bay-based Internet gun dealer who sold a weapon to the Virginia Tech shooter said Friday that he sold handgun accessories to the man who killed five students at Northern Illinois University.

Eric Thompson said his Web site, www.topglock.com, sold two empty 9 mm Glock magazines and a Glock holster to Steven Kazmierczak on Feb. 4, just 10 days before the 27-year-old opened fire in a classroom and killed five before committing suicide.

Another Web site run by Thompson’s company, www.thegunstore.com, also sold a Walther .22-caliber handgun to Seung-Hui Cho, who killed 32 people in April on the Virginia Teach campus before killing himself.

“I’m still blown away by the coincidences,” Thompson said Friday. “I’m shaking. I can’t believe somebody would order from us again and do this.”

His company, TGSCOM, Inc., shipped the order on Monday and records of the sale provided to The Associated Press by Thompson show Kazmierczak received the order on Tuesday.

Kazmierczak carried a rifle and three handguns into the classroom Thursday. Thompson said he had no idea whether the shooter used the holster or magazines purchased on the Web site.

Each magazine can hold 33 bullets, said Thompson, who added his site did not sell Kazmierczak any bullets or guns.

Kazmierczak purchased two of the weapons used in the shooting – the pump-action Remington shotgun and a Glock 9mm handgun – legally on Feb. 9 in Champaign, Ill., where he was a student, authorities said.

Thompson said he checked his sales records after the name of the shooter was made public on Friday. The records show $105.62 in items were shipped to an apartment in Champaign and signed for by someone other than Kazmierczak.

Thompson said he contacted the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives within five minutes of realizing the latest connection shortly after 9:30 a.m. Friday.

The Web site is well-known among gun users on the Internet so it is not surprising that someone looking for accessories for a Glock would find it, Thompson said. But being tied to both of the shootings is “unnerving,” he said.

“I still feel just absolutely in shock,” he said. “I feel like I was run over by a truck.”

Thompson said he has no way of knowing whether Kazmierczak found out about his Web site from the publicity it got after the Virginia Tech shootings, but the thought crossed his mind. Web traffic increased after that shooting, along with phone calls and threats, he said.

Thompson said he’s worried the same thing will happen this time around. But he decided to go public because he thought people have a right to know about the shooter.