Officials in the US state of Minnesota say the Federal Bureau of Investigation (FBI) has refused to co-operate with its investigation into the death of Alex Pretti.
Federal agents shot dead the 37-year-old intensive care nurse during a protest against immigration enforcement in the city of Minneapolis on 24 January.
Minnesota's Bureau of Criminal Apprehension (BCA) has accused the FBI of failing to hand over any information and evidence from its investigation into the shooting.
BCA Supt Drew Evans called the FBI's actions "concerning and unprecedented". The FBI has not yet responded.
Minnesota's BCA said it would "welcome a joint investigation" with federal officials.
