A sheriff's deputy at a drunken driving checkpoint was fatally shot in his patrol car Wednesday, and a suspect was killed by a SWAT team after barricading himself at home.

Sgt. Ron Harrison, a nearly 21-year veteran of the Hillsborough County sheriff's office, apparently tried to drive himself to the hospital after he was wounded about 1:30 a.m., Sheriff David Gee said.

A woman driving next to Harrison said he clipped her car as he sped down the road, his lights flashing, then he veered into a tree. Harrison, 55, was pronounced dead at a hospital.

"It's unclear if [the shooter] was in a vehicle or if he ambushed [the deputy] from the roadside," Gee said.

Click here for FOXNews.com's Crime center.

Around the same time, authorities received a call from another woman who said her boyfriend told her he had been in a shooting with a police officer, Gee said. Deputies found the man barricaded in his house, and he repeatedly fired at deputies before he was shot and killed, Gee said.

Harrison was the third deputy shot in Florida in the past 10 days and the second to die.

Click here for FOXNews.com's Crime center.