Miami - A Florida congresswoman says she is stunned by what she saw on video before the shooting of a black caregiver trying to coax his autistic patient into complying with officers.US Representative Frederica Wilson spoke to reporters after a news conference with police on Thursday. She says "the video is like a nightmare".The video shows Charles Kinsey lying on the ground with his arms raised, talking to his patient and police throughout the stand-off with officers, who appeared to have them surrounded. Police say officers had responded to a 911 call of a man with a gun threatening to commit suicide, and officers responded with that in mind. However, no gun was recovered.Wilson is promising to follow up with state agencies on their investigations to ensure "justice was done".Earlier, a police chief in Florida promised a transparent investigation into the shooting.North Miami Police Chief Gary Eugene said during a news conference on Thursday that the Florida Department of Law Enforcement was taking over the investigation at his request. The state attorney's office also was investigating.Eugene says bringing in an outside agency shows the department's commitment to objectivity in a sensitive matter. After the state's investigation is done, the department will do its internal investigation.