Police on Friday arrested a 50-year-old Long Beach man on suspicion of violently assaulting his girlfriend that led to her death, authorities announced.

Police believe John Buchanan assaulted 46-year-old Jaynie Sauter after an argument at their home near Chestnut Avenue and Seventh Street in the Willmore neighborhood the morning of Dec. 4.

“The argument led to the victim being violently assaulted by the suspect, which led to her death,” police said.

At about 5 p.m. that day, Sauter was found unconscious several blocks away near Pacific Avenue and West Fifth Street, according to a news release. She had minor visible injuries to her upper body and was taken to a local hospital. Paramedics told police Sauter was possibly the victim of an assault or accident.

Police did not find any evidence that indicated any weapons were used during the assault, spokeswoman Jennifer De Prez said.

Police were told on Dec. 7 that Sauter had died as a result of her injuries and homicide detectives immediately launched a suspicious death investigation. Detectives on Friday found and arrested Buchanan on suspicion of murder in San Fernando. He is being held in a Long Beach jail on a $2 million bail.

Detectives will present their case to the District Attorney sometime next week.

Police ask anyone with information on this incident to call Detectives Shea Robertson or Travis Harris at 562-570-7244. Anonymous tips submitted by calling 800-222-8477.