FOX LAKE, Ill. (AP) —
    The Illinois police officer whose fatal shooting last month set off a massive manhunt was shot twice with his own weapon, and there were signs of a struggle at the scene, the lead investigator said Thursday in releasing what he called carefully vetted details.
    Authorities, who have until now revealed little about their investigation, confirmed for the first time that Fox Lake police Lt. Charles Joseph Gliniewicz was shot with his own weapon. He was struck by two rounds, one that hit his ballistic vest with the force of a "sledgehammer" and another that pierced his upper chest, said Lake County Major Crimes Task Force Commander George Filenko.
    But gunshot residue found on his hands was inconclusive as to whether Gliniewicz fired any shots himself, according to results that came back from the Illinois State Police crime lab in the last week or two.
    "The weapon could have been fired by Lt. Gliniewicz or he could have been in a close proximity of the weapon being fired," Filenko said.
    At a news conference Thursday, authorities revealed details they said they had concluded wouldn't harm the investigation. But Filenko refused to reveal other key information, including how many times Gliniewicz's gun was fired in total and whether any of the DNA they are examining was found on his gun. He also would not provide any details on what the signs of the struggle were.
    Gliniewicz was found Sept. 1 after he radioed that he was pursuing three suspicious men in a remote area of the village south of the Wisconsin-Illinois state line. Investigators believe he was in the area because the village recently purchased the property and there had been reports of vandalism and trespassing.
    Despite a wide search and a month of detective work, police haven't made any arrests, identified any suspects or come up with a possible motive. Questions have swirled around the investigation — particularly since the county coroner said he has been unable to rule the 52-year-old Gliniewicz's death a homicide, suicide or an accident.
    Filenko said Thursday that the coroner and the pathologist who examined the officer's body both concluded the first shot struck his vest with such force that it likely incapacitated him. The second shot is believed to have been the fatal hit.
    Filenko emphasized the investigation was "strictly" being conducted as a homicide probe, though he acknowledged detectives weren't ruling anything out, including the possibility of suicide.
    The commander also said nine unidentified DNA samples were found at the scene on a variety of items that the officer had with him. Detectives working to identify the sources of that material have taken more than 100 samples from anyone who might have had contact with the officer, including from police who were close to the scene, Filenko said.
    They were also running some of those samples through a national database in hopes of a match. It was impossible to tell whether the traces of DNA were from the day of the officer's death or prior to it, he said.
    Asked whether any of it could have been left behind by someone walking a dog in the area, Filenko said, "Not likely."
    Investigators have also returned to the scene to recreate possible escape routes, including hunting trails, Filenko said in a newspaper interview a day earlier.
    It is a marshy area that Filenko described as being like quicksand in some types of weather. He became defensive when a reporter asked why police had not discovered footprints or tire marks that could point to people fleeing the scene.
    "Sir, if you went out and looked at the area, you tell me where you could see footprints," Filenko said.