A Roseville man’s belief that his wife was having an affair with her co-worker may have been the reason he shot and killed the man and then himself outside her workplace, authorities said Friday.

Roseville police responded to a report of a shooting with two men down at 4:15 p.m. Thursday near the loading dock area of CPI Card Group, a plastic card printer located at 1975 W. County Road B2, a few blocks from the Rosedale Shopping Center.

Police say Cheng Vang, 44, and his wife, Yong Vang, 37, both from Roseville, traveled to the business, where she works, to meet with her co-worker Joseph Yang, 33, of Brooklyn Park. Once there, Cheng Vang shot Yang multiple times with a semi-automatic pistol before turning the pistol on himself, police said. Yong Vang, who witnessed the shootings, went to the aid of her husband before police arrived.

The details of the meeting are under investigation, but authorities said in a news release they believe it was prearranged. Yang had a pen and paper documents when he was killed. Near Cheng Vang’s body, investigators found the pistol, which police determined he purchased legally in May.

Nearby surveillance cameras showed the Vangs arriving and parking on the east side of the loading docks with Yang arriving moments later and parking parallel to them. With the surveillance camera triggered to record only large object movements, the image stopped shortly after both Cheng Vang and Joseph Yang exited their vehicles and met.

“Preliminary investigative interviews indicate Cheng Vang may have believed Joseph Yang and his wife may have been involved in an extramarital affair,” Lt. Lorne Rosand, spokesman for Roseville police, said in a release. Thursday’s “meeting may have only been a ruse to lure Yang to a familiar location. Police speculate that once at CPI Card Group, Vang may have requested Yang to sign documents as a distraction in order to murder him.”

Autopsies determined that Cheng Vang died from a self-inflicted gunshot wound to the head and Yang from multiple gunshot wounds.

Yong Vang was not injured during the shooting and has been cooperative with police. She is not believed to be an accomplice. The investigation is ongoing.

Both Yong Vang and Joseph Yang were employed by CPI Card Group in an unknown capacity.

“The safety of our employees is of utmost importance and we are extremely saddened by this incident,” Diane Jackson, a spokeswoman for CPI Card Group, said in an e-mail.

The business has a counselor onsite for employees, Jackson said.

“Our thoughts and support are very much with our colleagues and the families of those involved in this incident as well as all of our colleagues in Minnesota,” she said.

CPI shares a large loading dock area with the shopping center that houses REI, Tuesday Morning, a furniture store and an urgent care clinic.

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