A former Bridgeport police detective is in critical condition at a Florida hospital after police say he tried to murder his ex-fiancee and then shot himself.

Police say Billy Chase ambushed Lynn Herriott as she headed to her car in Jacksonville, Florida, shot her six times and then shot himself. Officials say both are now clinging to life.

Chase was an undercover detective for the Bridgeport Police Department and feds in the 1980s and 1990s. During his tenure, he gained notoriety for infiltrating mafia rings and drug organizations. Chase was forced to abruptly leave this job in the 1992 after several high-profile death threats.

Lennie Grimaldi, the author of the blog Only in Bridgeport, was close to Chase and wrote a book about him in the mid-1990s. He says Chase was never able to escape the demons of the job.

"Bridgeport police officers will tell you, there were still threats on his life for a number of years," Grimaldi says. "So he lived a life of isolation for a long time."

Herriott had filed three different restraining orders against him for domestic violence. Her sister, Natasha Bridges, says Chase broke into Herriott's house months ago and tried to kill her.