A Louisiana state trooper was shot to death while typing reports inside his patrol car early Saturday morning in Prairieville, but another 15 hours would pass before another officer found him unresponsive — a delay that agency leaders called "absolutely unacceptable" and "a perfect storm" of communication failures. 

During a press conference Monday afternoon, State Police Col. Lamar Davis released more information about the alleged ambush of Master Trooper Adam Gaubert, which added to the mayhem and tragedy of a massive multi-parish manhunt for Matthew Mire, the suspect in that shooting and several others. 

Davis said the chaos of the manhunt likely led to Gaubert going undiscovered for the next 15 hours. He said troopers were maintaining radio silence during the search, meaning non-emergency radio calls were suspended, the Advocate reports.

Normally, Gaubert would have signed off around 6 a.m. when his overnight shift ended, telling his colleagues "10-7" over the radio. But those calls are suspended during major emergencies like a manhunt or other critical incident, per agency protocol, Davis said.

The night of his death, officials believe Gaubert had responded to a traffic accident and then parked in a secluded spot behind a bank to complete his report.

Investigators believe Mire ambushed Gaubert and shot the trooper multiple times before committing another double shooting at a house less than a mile away, Davis said Monday. 

Davis said State Police are implementing a number of changes in response to what happened, though some technology upgrades were already underway. He said this tragedy made it abundantly clear that the agency needs more safeguards to make sure all troopers are accounted for. Among the changes underway: expanded GPS coverage of patrol vehicles, including alerts whenever someone stays dormant too long, and more location monitoring by supervisors.