COLLEGE PARK, Md. (AP) — Investigators didn't find any evidence of a fight between a Maryland police officer and the handcuffed man he is accused of fatally shooting in the front passenger seat of his patrol car, police said in a report on a murder charge against the officer.

Prince George's County Police Cpl. Michael Owen Jr. fired seven shots at William Howard Green and struck him multiple times, said the report on Monday's shooting.

Owen had handcuffed Green, 43, of Washington, D.C., behind his back and placed him in the cruiser after responding to a traffic accident and finding him sleeping in his vehicle, apparently under the influence of an unknown substance, said the report released Wednesday.

About five to 10 minutes after Owen placed Green in his cruiser, a witness heard gunshots and saw the wounded man still seated in the front passenger seat with his hands cuffed behind his back, police said.

Investigators did not find any weapons in Green's possession or in his vehicle. Witnesses told officers Green had struck their vehicle, police said in a news release.

Owen a 10-year veteran of the force, was arrested Tuesday on charges of second-degree murder, voluntary and involuntary manslaughter, first-degree assault and use of a firearm in the commission of a crime of violence.

Owen, 31, of Accokeek, Maryland, is scheduled to appear in court on Wednesday afternoon for a hearing on whether he can be freed on bail.

Prince George's County Police Chief Hank Stawinski said during a news conference Tuesday that he asked his special investigations response team to file the charges. Stawinski called the announcement the most difficult of his tenure as police chief.

“I am unable to come to our community this evening and provide you with a reasonable explanation for the events that occurred last night," the chief told reporters. “I concluded that what happened last night is a crime.”

During an earlier news conference, police department spokeswoman Christina Cotterman had said two witnesses told police they either saw or heard a struggle before the shooting. Cotterman also said officers smelled PCP and believed the man was under the influence of that drug.

However, Stawinski later said PCP did not appear to have been involved and that no account of a struggle in the cruiser could be corroborated.

"There are no circumstances under which this outcome is acceptable,” Stawinski said. “You have my assurance that all our methods and practices will be examined as this investigation proceeds.”

The shooting wasn't caught on body-camera video because the officer didn't have one, police said. Investigators were looking for surveillance cameras in the area that may have recorded the shooting.

In a news release, police said a department directive permits officers to transport arrested suspects in the front passenger seat of patrol cars that don't have partitions. Owen's cruiser did not have a partition.

Owen had been placed on administrative leave prior to the announcement that charges would be filed against him.

Owen is black. A police department spokeswoman wouldn't specify Green's race, citing department policy.

Owen has been involved in at least two other shootings during his time on the force. In 2011, he fatally shot a man who pointed a gun at him after Owen left an event at police headquarters, the department said. Owen was placed on administrative leave after that incident, but there is no indication whether additional action was taken.

In 2009, Owen was off-duty when someone tried to rob him outside his home, The Washington Post reported. Police officials said the would-be robber fired, but Owen was not hit and returned fire. The assailant fled, according to police.

Prince George’s County State’s Attorney Aisha Braveboy said in a statement Tuesday that her office will conduct a "thorough and independent investigation.”

“We will seek truth, and will vigorously pursue justice in a way that is fair and responsible,” Braveboy said. “Once we have received all information and completed our own investigation and analysis, I assure you that my office will be transparent and accountable to the public about our findings and how we will move forward.”

Deborah Jeon, legal director for the the American Civil Liberties Union of Maryland, said in a statement that there is no reason for an officer to shoot a handcuffed suspect multiple times inside a patrol car. Jeon called it “completely unacceptable” that Prince George's County's police department doesn't equip all its officers with body cameras.

“These deaths are completely preventable,” Jeon said. “Police characterize them as unavoidable, but they are not. And body camera footage will show that.”