SEYMOUR, Ind. (AP): Police say they don’t know how the gunman got his weapon past security before a workplace murder-suicide in southern Indiana.

Seymour Police Chief Bill Abbott said Friday that security video didn’t show 37-year-old Qing Chen with the 9 mm Glock handgun when he entered Cummins Inc.’s Seymour Engine Plant before the shooting Thursday morning.

An autopsy Friday morning showed Chen’s direct supervisor, 49-year-old Ward Edwards of Columbus, died of multiple gunshot wounds and Chen died of a self-inflicted gunshot wound. Both men died instantly.

Abbott said Chen had a permit to carry a gun and purchased the Glock in 2012 in the Indianapolis suburb of Plainfield. Investigators recovered four other guns from Chen’s Seymour apartment.

Abbott says Chen was a Chinese national in the U.S. on a five-year work visa.