A SWAT standoff in unincorporated Pinellas County has ended with a deputy shot and a sex offender dead.

Pinellas County deputies responded to a home located in the 5100 block of 80 Way N. on Wednesday morning.

Sheriff Bob Gualtieri said Susan DiFabbio called police Wednesday morning after an argument with her son, 24-year-old Jeffrey Falsey.

"What triggered it this morning was Falsey wanted his mom to go get donuts and she wouldn't do that," said Gualtieri.

DiFabbio called police after a heated argument with Falsey because she refused to get him donuts

When deputies arrived at the home, DiFabbio greeted deputies outside and two deputies went to the home to talk to Falsey.

The sheriff said Falsey invited them inside, but the deputies sensed something was not right and refused to enter for their safety. Falsey then started firing shots.

"It was a little bit before 9 and I heard, pop, pop, pop," said neighbor Gayle Gerbes.

Another responding deputy was shot in the leg during the standoff. He is in good condition with non-life threatening injures at Bay Front Medical Center.

According to Gualtieri, Falsey has a history of mental illness.

"All he was interested in was killing people," he said.

Falsey fired, at minimum, 30 rounds in the direction of the deputies.

Inside the home, Falsey shot and killed Daniel Kulwicki with a shotgun. According to the sheriff, Kulwicki is a registered sex offender and Susan's fiancé.

Jeffrey was not happy Kulwicki was living with his mother, the sheriff said.

Falsey had a 12 guage shotgun, a TEC 9 semi-automatic pistol, a .45 caliber handgun and a 223 rifle with "a bunch of ammunition," the sheriff said.

He has been charged previously with domestic battery against his mother.

The sheriff said Falsey legally owned the guns.

He is now in custody.

Shots fired in St. Pete, SWAT on scene

Story Developing. Stay with ABC Action News for updates.