A longtime Hillsborough County Sheriff's Office deputy killed his wife, daughter and granddaughter before taking his own life, Sheriff Chad Chronister confirmed Wednesday.

Chronister said deputy Terry Strawn, 58, retired two years ago and was later hired back to work as a resource deputy at Valrico Elementary School, where his granddaughter attended.

Investigators said Strawn came over the radio and indicated he had already harmed his family members at two different locations and planned to end his own life near Plant City High School. 

Chronister said a supervisor got on the radio and tried to calm Strawn and de-escalate the situation. Three responding deputies found him on the east side of Plant City High School off-campus but were unable to convince him to stop.

"Unfortunately, the deputy took his own life on scene in front of the other deputies," Chronister said.

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Chronister identified the victims as 54-year-old Theresa Strawn (wife), 32-year-old Courtney Strawn (daughter) and 6-year-old Londyn Strawn (granddaughter).

The sheriff said all three died from gunshot wounds. Chronister said Strawn used his service weapon.

Terry Strawn had been with the sheriff's office since 1991. Chronister said they had just told him he was being hired back permanently for the school resource officer position. Chronister said Strawn seemed excited about the news.

The sheriff said during the radio transmission Strawn talked about how much he loved the sheriff's office but alluded to some financial and health issues. Chronister said he is unaware of what those issues were.

Chronister said Strawn said in the transmission that he "wanted us to know that depression is real" and that he "wanted to go be with his family."

The sheriff said Strawn also has other family members employed with the Hillsborough County Sheriff's Office. 

Chronister said grief counselors are being made available for the sheriff's office and Valrico Elementary School. 

Hillsborough County Public Schools issued a statement Wednesday afternoon:

The staff and families at Valrico Elementary are devastated by this unthinkable tragedy. Londyn was a first-grade student at the school. She loved to learn and was excited about reading and math. She had a kind spirit and always helped classmates.

The news came as a shock to everyone at the school and they are working through their grief. Our district has crisis team members at the school to work with staff members. We have let parents know crisis team members will be at school Thursday for any students who want to talk.

Spokesperson Tanya Arja said Plant City High School was on lockdown early Wednesday morning before students arrived after hearing reports of shots fired near the campus. Arja said the school is back to normal operations. Arja said some staff may have been on campus at the time, but no students were there.

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If you have suicidal thoughts, contact the Crisis Center of Tampa Bay at 211 or the National Suicide Prevention Lifeline at (800) 273-8255. 

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