WASHINGTON (Reuters) - A Washington police officer will face no charges for fatally shooting an unarmed black motorcyclist who rammed his cruiser after a high-speed chase, U.S. prosecutors said on Wednesday.

The September 2016 shooting death of Terrence Sterling, 31, triggered demonstrations in the U.S. capital amid anger over police killings of African-Americans across the United States.

“There is insufficient evidence to pursue federal criminal civil rights or District of Columbia charges” against the officer who shot Sterling, the U.S. Attorney’s Office said in a statement.

Hassan Murphy, a lawyer for the Sterling family, did not immediately respond to a request for comment.

Mayor Muriel Bowser said Washington’s Metropolitan Police Department had asked for the resignation of the officer involved, who did not have his body camera on in violation of protocol.

“I do not believe there can be real accountability if the officer remains on the force,” she said in a statement. The officer is on administrative leave and faces an internal department review of the shooting.

Sterling, a resident of Fort Washington, Maryland, was on a motorcycle when he pulled in front of a police cruiser at a red light early on Sept. 11, the prosecutors’ statement said.

Sterling glanced at the officers, then raced through the red light. The police car pursued Sterling, who reached 100 miles per hour (160 km per hour) as he sped through red lights over a 25-block route, the statement said.

Sterling stopped at an intersection and the cruiser blocked his path. When the officer began to get out of the passenger side, Sterling rammed into the passenger door.

The officer fired two rounds, hitting Sterling in the right side and neck. He was pronounced dead at a hospital.

Sterling had a blood alcohol level of 0.16, about twice the legal limit for the District of Columbia, and tested positive for THC, the active ingredient in cannabis, the statement said.

The officer was not identified by police, prosecutors or the mayor. A wrongful death lawsuit filed by Sterling’s family against the department has named him as Officer Brian Trainer and alleges that Sterling posed no threat to him.