ANKARA

The FBI has formally refused to share evidence and information with Minnesota investigators in the killing of Alex Pretti, the state’s top investigative agency said Monday, hampering efforts to probe the fatal shooting by federal agents.

The Minnesota Bureau of Criminal Apprehension (BCA) described the federal government’s refusal as “concerning and unprecedented,” according to the agency. The FBI notified the BCA that it would not provide access to any evidence it has collected in the Jan. 24 shooting death of Pretti in south Minneapolis.

The agency said it has reiterated requests for evidence and information not only in Pretti’s shooting but also in the federal killing of Renee Good and the shooting of a Venezuelan national last month, but has received no cooperation from the FBI.

“Our agency has committed to the FBI and Department of Justice that should its stance change we remain willing to share information that we have obtained with that agency and would welcome a joint investigation,” BCA Superintendent Drew Evans said. He added that the agency will pursue “all legal avenues” to obtain relevant evidence.

CBS News reported that federal agents shot and killed Pretti and initially prevented BCA agents from collecting evidence at the scene. The BCA obtained a temporary restraining order blocking the Department of Homeland Security from destroying or altering evidence, but a federal judge later lifted it.

Hennepin County Attorney Mary Moriarty told WCCO, a CBS Minnesota station, on Sunday that she plans to send a written demand for evidence to the Justice Department and Homeland Security.

Pretti’s family has called for a joint state and federal investigation into his killing.