SALEM, Ore. (AP) _ A taxi driver whose anguished screams could be heard over the dispatch radio was fatally shot in the back of the head before her cab crashed into a tree, officials said Monday.

Michelle Howard, 36, was found dead inside the cab after Sunday's crash near Brooks, just north of Salem.

The man accused of abducting and killing her, 29-year-old Daniel Wayne Kirkland of Keizer, was arrested while running along a country road nearby. Charges against him include aggravated murder, kidnapping and robbery.

Howard died of a wound to the back of the head from a large caliber bullet, said Dr. Nikolas Hartshorne, a deputy state medical examiner.

Evidence indicates the shot or a struggle just before the shooting may have caused the accident, Hartshorne said. He said there was no sign the victim had been sexually assaulted.

Howard, a part-time college writing instructor who had worked for Yellow Cab Co. for just two weeks, was on her first fare of the day _ a man who asked to be driven from Salem to neighboring Keizer.

``The person did not ask for her by name or number,'' said company president Dan Harbaugh. ``She was sent there totally at random. It could have just as well have been a man driver.''

Cab company dispatchers called police after hearing Howard screaming into the car's radio.

``They weren't sure what she was screaming, but it was frightening,'' said sheriff's Deputy Randy Corey. ``They tried reaching the cab and couldn't, so they called for help.''