An Oroville man is in custody for assaulting his girlfriend and leaving her in critical condition, and authorities now say she is pregnant.

43-year-old Olabku Jones was arrested Monday afternoon after investigators spent the day combing a home on Spencer Avenue in Oroville collecting evidence.

He's being charged with felony domestic violence causing great bodily injury.

Jones' live-in girlfriend, 33-year-old Abby Tucker, remains in critical condition at a Sacramento hospital. She is four to six weeks pregnant.

Oroville Police Lieutenant Al Byers says that Tucker may not survive her injuries.

"The information we have is that she does have life threatening injuries," Byers says, "and her chance of survival is not that good at this point."

He adds that if she doesn't survive, it could be treated as a murder.

"If it does turn into a homicide case, we're prepared to move forward with that," Byers says.

District Attorney Mike Ramsey says Jones will be in court Wednesday for arraignment, and whether Tucker survives the night will determine what charges are brought against him.