GRAND JUNCTION, Colo. -- Mesa County sheriff's investigators are talking with associates and friends of a missing Grand Junction woman, as they look for the mother of three who's been missing since last week.

Paige Birgfeld, 34, has not been seen or heard from since Thursday.

Sheriff's officials are also looking for any possible evidence in the vicinity of a parking lot where Birgfeld's car was located Sunday night. The front section of the car had been set afire.

Authorities also want to know more about messages Birgfeld reportedly posted to a Web site. The postings indicated she feared the return of her ex-husband, Rob Dixon.

Birgfeld wrote in March that her children asked if their dad was going to kill her.

But Birgfeld's father, Frank Birgfeld of Denver, said it does not appear Dixon has been in the Grand Junction area recently.

About three dozen relatives and friends held a candlelight vigil Monday night to pray for Birgfeld's safe return.

Her car was found ablaze Sunday night in a parking lot about two miles from her home. Mesa County sheriff's Lt. Jim Fogg said authorities have not ruled out a random act of vandalism.

A bloodhound was used to try and track any scents from the car out of the industrial area where it was found, but it was not known if that was successfull.