OCEANSIDE, Calif. – A man cleaning his gun accidentally shot through the floor of his Oceanside apartment Tuesday evening, critically injuring a woman who was watching TV.

Police responded to the 1300 block of Bush Street around 11 p.m. after a man called and said he was cleaning his 9mm Glock handgun and accidentally shot through the floor of his apartment, Oceanside police spokesman Tom Bussey said.

“I heard a huge ‘boom’ then someone screaming — then rushing down the stairs very quickly,” said Shelly Duda, a neighbor.

The woman was sitting on the couch when she was hit in the leg by the bullet. She was unconscious and barely breathing when first responders arrived. Paramedics transported the woman to a local trauma center and she is currently in critical care, Bussey said.

The victim is from Huntington Beach and was apartment sitting for her daughter and son in-law who were in Anaheim.

“We were both sleeping, had our phones off — we didn’t know about it until this morning. Once we found out, we immediately came back down,” said Samuel Stansberry, the victim’s son in-law.

The shooter has not been taken into custody, Bussey said.

The shooter was giving aid to the victim when officers arrived.

“He was in total shock. He couldn’t believe it happened. He was freaked out, totally,” said Duda.

The shooting remains under investigation.