The Roman Catholic bishop of Phoenix has been arrested in a deadly hit-and-run accident after police traced a license plate number to his car and found the windshield caved in.

Bishop Thomas O'Brien (search), 67, was booked Monday on a charge of leaving the scene of a fatal accident, a felony. He was released on $45,000 bail and declined to answer questions when he left jail.

O'Brien told police he thought he had hit a dog or a cat or that someone had thrown a rock at his vehicle.

His arrest came two weeks after prosecutors announced that he had relinquished some of his authority in an unprecedented agreement that spared him from indictment on obstruction charges for protecting priests accused of child molestation.

The accident occurred after dark Saturday night, when 43-year-old Jim Reed was struck by two cars while walking across a street in the middle of the block about three miles from the bishop's home. Both cars drove off.

Police traced a license plate number to O'Brien's car and found the windshield caved in Monday morning. O'Brien's attorney, Jordan Green, declined to comment.

Sgt. Randy Force, a police spokesman, said O'Brien wasn't being charged with causing the crash because Reed was jaywalking. "If the bishop had remained at the scene, in all likelihood he would not have been charged with any crime," Force said.

If found guilty of leaving the scene but not responsible for the death, O'Brien could face punishment ranging from probation to less than four years in prison. A defendant found responsible for such a death could face more than eight years.

O'Brien was hospitalized briefly after his arrest. A hospital spokeswoman would not say why he was taken to the hospital. Diocese spokesman Jose Robles would only say the bishop "was very exhausted." The Arizona Republic said he was suffering from high blood pressure.

At St. Thomas Church, Catholics attending Monday evening Mass prayed for O'Brien and for the man killed in the accident. O'Brien has been the spiritual leader of 430,000 Catholics in Arizona since 1981.

"If anything, something wonderful will happen," Anna Becerra said as she left the service. "There will be healing and a tremendous amount of prayer for the people in the community."

Police said in court documents that O'Brien had driven the car to Mass on Sunday and to visit his sister in Scottsdale. He had also made a call about having the windshield fixed, police said.

The documents said a priest had informed O'Brien on Sunday night that police were looking for him but that the bishop never contacted authorities. Police said they had no information on the second car.

Force said alcohol wasn't a focus of the investigation but also noted that there would have been no way to test for it by the time police talked to O'Brien.

The bishop's tan Buick with its broken windshield was taken away by police, Sgt. Laurie Williams said. A search warrant called for any evidence of blood, hair or glass samples, Williams said.

Williams said O'Brien had told police he was returning home after a Mass when he thought he had hit an animal or that someone had thrown a rock at his car.

In a statement, Monsignor Richard Moyer, the diocese's chief of staff, said the diocese would cooperate with the investigation.

"The sympathy of all of us in the Diocese of Phoenix (search) as well as our prayerful support goes out to the victim's family," Moyer said.

Monsignor Francis Maniscalco, spokesman for the U.S. Conference of Catholic Bishops (search), declined to comment on O'Brien's arrest.

In the agreement with prosecutors announced earlier this month, O'Brien admitted that he allowed priests to work with minors after he knew of sexual misconduct allegations against them and that he transferred them to ministries without telling their new supervisors.

Under the deal, O'Brien agreed, among other things, to appoint the church equivalent of a chief of staff to supervise the enforcement of the church's sexual misconduct policies.

Some U.S. Catholic bishops have been arrested during political protests. And in 1985, the former president of the national bishops conference, Archbishop John R. Roach of St. Paul and Minneapolis, pleaded guilty to drunk driving and was sentenced to 38 hours in jail plus substance abuse treatment and a fine. He served another decade as archbishop.