The driver troopers accuse of hitting and killing a toddler in Key Largo early Tuesday is a former Pennsylvania police officer who was convicted 17 years ago of conspiring to rob a drug dealer to finance a South American treasure hunt.

Edward Krajewski worked for the Lower Southampton Police Department when he was convicted in 1996 of conspiring with another man to rob a Philadelphia drug dealer, according to Philadelphia Inquirer newspaper reports.

Krajewski served not quite six years in prison and was released March 10, 2002, said Pennsylvania Department of Corrections spokeswoman Susan Bensinger.

Krajewski had reportedly been trying to find sunken silver bars off the coast of Ecuador that he said belonged to Sir Francis Drake, those reports say.

That hunt never got off the ground after the attempted robbery was stymied by investigators.

Florida Highway Patrol investigators allege Krajewski was driving the 2013 Hyundai Sonata that struck 2-year-old Austen Mark Alward just after midnight Tuesday.

Krajewski told deputies he thought he had hit an animal, according to a Sheriff's Office report.

Whether drugs or alcohol were a factor remains under investigation.

Austen's mother found his body at 12:27 a.m. near Mile Marker 99.5, about three feet from the highway, according to a Florida Highway Patrol press release and Sheriff's Office report.

The child reportedly unlocked doors and got through a gate and leave the Sunset Boulevard property while his parents slept.

Deputies stopped Krajewski at 12:55 a.m. at Mile Marker 26.

State Attorney Catherine Vogel said she had not yet decided whether Krajewski or Alward's parents will face any criminal charges.

The Highway Patrol had not completed its investigation as of Friday, said Lt. Cathy McKinney.

alinhardt@keysnews.com