A suburban Dallas police officer who shot and killed a teenage burglary suspect and wounded another boy while off-duty was released from jail on bond Thursday, authorities said.

Ken Johnson, a Farmers Branch police officer, was arrested Wednesday on murder and aggravated assault charges in the shootings Sunday in Addison. He posted $150,000 bond and left jail early Thursday, according to Melinda Urbina, of the Dallas County Sheriff's Department.

According to Addison police, Johnson, 35, was off-duty when he saw 16-year-old Jose Raul Cruz and the other boy burglarizing a vehicle at his apartment complex. He confronted them, they fled and he gave chase, catching up to them when their vehicle spun out about a half-mile away. An altercation ensued, during which Johnson shot the duo.

Cruz died at the scene. Police haven't released the name or age of the wounded boy, referring to him only as a juvenile. But a police affidavit obtained by WFAA-TV in Dallas identifies him as Edgar Rodriguez Arevalo and says he was a passenger in the car. It says he suffered gunshot wounds to his hands and head and was hospitalized.

Authorities haven't said whether the juveniles were armed or whether they might pursue any charges against the wounded boy. Johnson wasn't injured.

Johnson's attorney, Chris Livingston, has said the officer feared for his life and shot the duo in self-defense. Livingston didn't immediately respond to a phone message left Thursday seeking additional comment.

Addison police Chief Paul Spencer said in a statement Wednesday that there was "probable cause" to arrest Johnson, but that the investigation will likely take several more weeks to complete.

Farmers Branch police spokesman David Laisure declined to comment Wednesday, deferring questions to Addison police. Spencer previously said that Johnson had no disciplinary record. He also noted that department policies don't allow off-duty officers to chase suspects in their own vehicles.

Over the last decade, law-enforcement agencies have recorded roughly 1,000 fatal shootings each year by on-duty police, according to Philip Stinson, an associate professor at Bowling Green State University in Ohio who studies police crime. An average of fewer than five each year resulted in murder or manslaughter charges against officers, Stinson found.

Of the 47 officers charged from the beginning of 2005 through the end of last year, about 23 percent were convicted, Stinson found.

But with no national database tracking police shootings, even these numbers are largely speculative, Stinson said. And he said it's unknown how many off-duty officers are involved in fatal shootings each year.

Based on newspaper and other accounts, it appears there are about six cases each where an off-duty officer is charged in a shooting death, Stinson said.

"The policing subculture is so dynamic, so ingrained in these guys that you can't turn it off when you go home at night," he said.

According to the Texas Commission on Law Enforcement, Johnson has worked for Farmers Branch police for a year. He worked as a peace officer for Dallas Area Rapid Transit for almost eight years before that.