Updated

Authorities believe a staff nurse killed a resident at the Pennsylvania nursing home where she worked and then herself.

Officials in Lackawanna County say the 42-year-old licensed practical nurse apparently brought a semi-automatic handgun to her Monday night shift at Abington Manor in South Abington Township. Police Chief Robert Gerrity says she apparently shot the 79-year-old man and then turned the gun on herself at about 5:30 p.m. Monday.

Gerrity says the motive is unknown. Gerrity says the nurse had worked there since 2011 and the patient had lived there about two years. Their names weren't released pending notification of relatives.

Nursing home spokeswoman Jeanne Moore says in a statement that officials are "shocked by the tragedy" and cooperating with investigators.