A woman wanted for questioning in a California missing persons case was killed and her husband was arrested following a 40-mile chase and shootout in northern Colorado, authorities said.

Nicholas Vovos (search), 22, of Lake Forest, Calif., was arrested after the shootout Sunday at a gas station just off Interstate 76 at Lochbuie, about 25 miles northeast of Denver.

His wife, Deborah Sue Miller Vovos (search), 39, was killed. It was unclear whether she was shot by police or turned a gun on herself, Police Chief Steve Davis said.

"We're still sorting out who fired what," Davis said.

A sheriff's deputy suffered cuts from a windshield shattered by a shotgun blast fired by Nicholas Vovos, authorities said.

The couple were wanted for questioning in the disappearance of Carolyn Dunn Avdeef (search), 62, of Lake Forest, Calif., who was last seen by her family June 15. She remained unaccounted-for.

Law enforcement officers had been on the watch for Avdeef's car, which authorities said was taken by the Vovoses, who both had criminal records in California.

The vehicle was chased by Wyoming State Patrol (search) officers near Laramie on Saturday night but escaped.

Then a policeman in Wiggins, 40 miles north of Lochbuie, spotted the car Sunday morning and a chase ensued.

Police in Lochbuie put down a strip of spikes to stop the car, but it continued six miles on its rims before coming to a halt in the gas station.

"I saw a guy shooting at police," witness Sara Skretta, who lives nearby, said. "He was shooting at the police cars. It looked like he shot twice and the police shot about six times."

She said that when the shooting stopped, she looked outside again and saw paramedics trying to revive a woman who had been a passenger in the bullet-riddled car.

Nicholas Vovos was being held without bond Monday.

The Vovoses had lived at Avdeef's home, and California authorities believe the couple stole her car and her credit cards. Deborah Vovos was the daughter of Avdeef's roommate.