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Input: Baltimore's police commissioner  asked the FBI on Friday to take over an investigation into the fatal shooting of a city homicide detective on the eve of his scheduled testimony to a federal grand jury looking into alleged police corruption.
 Commissioner Kevin Davis  made the request a day after a U.S. District Court grand jury in Baltimore indicted former Sgt. Wayne Jenkins on charges of duping colleague Sean Suiter in 2010 into "discovering" drug evidence Jenkins had planted in a car.
 Davis  said police  the FBI and federal prosecutors don't believe there's a connection between Suiter's planned testimony and  his  death Nov. 15.
 Davis  suggested at a news conference  however  that the FBI and U.S. attorney's office haven't been forthcoming with information that could help  his  investigators in probing Suiter's shooting.
"Right now  there is no DNA evidence or other forensic evidence â blood  etc. â that identifies the perpetrator  " Davis  said.
"The circumstances surrounding Detective Suiter's killing are significantly complicated by the fact that he was to appear before a federal grand jury the following day "  Davis  wrote in a letter Friday to FBI Director Christopher Wray. "I am growing increasingly uncomfortable that my homicide detectives do not know all of the facts known to the FBI or USAO that could  if revealed to us  assist in furthering this murder investigation."
 Davis  has said  he  didn't know about Suiter's scheduled testimony until nearly a week after  his  death  and that  he  learned of the latest indictment of Jenkins at the same time as the media.
 Davis  said  his  department is continuing to run down leads in Suiter's killing and is not ruling out anything  including homicide by a still-unknown person  suicide or a conspiracy.
"We will follow the evidence where the evidence goes. ... We are not going to discount any possibility whatsoever "  he  said.
At the same time   Davis  distinguished between "probabilities" and "possibilities " and repeatedly referred to Suiter's death as a "murder."  He  also said  as  he  had in the past  that physical evidence  including a garbled radio transmission from Suiter that ended with the sound of a gunshot  and the condition of the detective's clothing  indicates  he  was engaged in a struggle before  he  died.
Police have said Suiter and his partner were in a crime-ridden neighborhood seeking information involving a 2016 triple homicide when Suiter approached the suspicious man in a vacant lot  leading to a confrontation in which he was shot in the head. His partner can be seen on private surveillance video taking cover across the street  according to  Davis .
With no arrests in the case  despite a $215 000 reward  and a churning rumor mill about the death and the investigation   Davis  said  he  also sought to address public concerns.
"I understand the anxiety  and folks say  'Something just doesn't jive here.' ... So  in the best interest of the integrity of the investigation  I just believe it's the right thing to do to ask the FBI to assume the lead "  Davis  said.

Baltimore police ask FBI to take over investigation into cop's death