Graphic Video: Detroit Police Station Gunfire

DETROIT -- A graphic 68-second video released by Detroit police Friday shows a gunman striding into one of the city's precinct stations, spraying volleys from a shotgun at surprised officers before being fatally wounded within inches of three of his victims.

The grainy surveillance video with muted color from Sunday's rampage at the city's 6th Precinct was made public only after members of the city's police force had seen it, Police Chief Ralph Godbee said.

The video shows Lamar Moore, 38, walking into the precinct and past the building's raised front desk. He pulls a shotgun he had concealed along his right side and opens fire down a hallway. He's then seen firing more shots down the hallway as he reverses his steps back into the middle of the lobby.

Moore then lunges head-first over the counter where two officers and the precinct's off-duty commander had taken cover, firing shots of their own in his direction.

The most graphic portion of the video shows Moore square off with Cmdr. Brian Davis - above the prone figures of two wounded officers - as they exchange shots with their weapons about a foot apart. Davis loses parts of two fingers from a shotgun blast and crumples to the floor. He twists around a smaller desk as Moore continues toward him, at one point hurling a trash can at the gunman.

Moore, himself wounded, attempts to maneuver toward Davis, but falls to the floor. He later died while being taken to an area hospital, Assistant Chief Chester Logan said.

Police have not determined a motive behind the rampage, which left four officers wounded. "There's nothing in this that makes sense at all," Godbee remarked.

Davis, the most seriously wounded, also was shot in the back. He and Sgt. David Anderson are expected to be released from the hospital soon. The other two officers were released earlier in the week.

"There are some tremendous acts of heroism in this video - to see officers perform in a spectacular way," Godbee said.

But, he added, "Suffice is to say the psychological damage that has been done to the officers there -- not only there but all across the department -- we've got some heavy lifting to do."

Police say they're instituting new security measures in the wake of the shooting, reports CBS News correspondent Elaine Quijano.

To see the dramatic video, click below: