A 7-year-old boy watched his father murder his mother and then kill himself during a custody exchange that went horribly wrong Friday afternoon, authorities said.

According to the Hillsborough County Sheriff's Office, Guillermo Garcia, 38, and Okariny Diaz, 33, met in the parking lot of a Village Inn about 1 p.m..

After getting into an argument, authorities said, Garcia shot Diaz "multiple times" and then turned the gun on himself.

Two other adults and three girls, ages 10 to 14, also witnessed the horrific murder-suicide.

Jessica Hernandez said she watched the shooting unfold at the restaurant at 8602 N. Dale Mabrey Highway from her apartment balcony across the street.

"I heard five gunshots and I thought it was fireworks at first," Hernandez said. "When I came out, I saw the lady on the floor, and when I looked, I saw the man shoot himself."

Authorities said Garcia arrived at the restaurant in a four-door Ford F-350 pickup truck and and parked next to a Chevrolet conversion van driven by Diaz. Garcia allowed the boy to get out of the truck and enter the van, which was also carrying two other adults and three girls.

Garcia then walked to the side of the van and began talking to Diaz. The conversation turned into an argument and then escalated to the violence.

Hernandez said she watched as the boy and a 10-year-old girl jumped out of the vehicle screaming. She said another woman also came out of the vehicle screaming.

"That's going to be a memory, unfortunately, they're going to have for the rest of their lives," sheriff's office spokesperson Col. Donna Lusczysnki said. "Seeing their parent ... one kill their other parent and then commit suicide in front of them, that's horrible for anybody to imagine that."

The other children in the van were not related to victims, authorities said.
 
Garcia and Diaz were never married. According to the Tampa Bay Times, court records show that a paternity test done in 2005 confirmed that Garcia was the boy's father.

Authorities say Garcia is from Pembroke Pines in south Florida but rents a Town 'N County home. Diaz lives in Tampa.

According to the Times, a leasing agent at a Town 'N County apartment complex said Diaz recently moved out because Garcia found out where she lived.