A case of domestic violence involving a soon-to-be divorcing couple ended tragically with the deaths of two young children and their father, according to Hernnado County Sheriff Al Nienhuis.

The sheriff said during a news conference Monday that Daniel Castrillon, 39, shot and killed his two children, Susana, 8, and Sabastian, 7, while they were sleeping during the weekend in their Brooksville home before turning the gun on himself.

"We are still trying to piece together more information, but it appears to be a case of domestic violence that, unfortunately, turned deadly and took a couple of innocent young lives," Nienhuis said.

According to authorities, Castrillon's wife, 34-year-old Luz Jimenez, filed for divorce and moved out of the Nodding Shade Drive home on Oct. 12.

Officials said Castrillon picked up the children from Chocachatti Elementary School on Friday. Jimenez tried to contact her husband and the children on Saturday and went to the home on Sunday but could not get in. She called authorities Sunday.

Authorities responded to the home in the 900 block of Nodding Shade Drive just after 9:30 p.m. Sunday. According to a witness, deputies approached the home with shields drawn. A short time later, the area was blocked off with crime scene tape.

Officials said the couple argued Friday at Jimenez's job and later that day Castrillon told his wife in a phone call he planned on returning to his native Colombia with the children.

According to Nienhuis, the children and Castrillon each died of a single gunshot wound to the head. Officials said the boy was found in his bed, while the daughter was found in bed with her father.

"It's very, very difficult anytime you have innocent children killed," Nienhuis said. "It's even worse they are killed by someone who is supposed to be there to take care of them."

Castrillon’s friends said they can’t even comprehend it.

“My wife and I can't believe this happened. Definitely didn't expect that,” said Jose Guerrero.

Guerrero said the two kids were sweet and full of life.

"Excellent, excellent kids. Very smart, very smart kids and he was a good dad,” he said.

Kayla Hundley lives across the street and said she would see Castrillon and his kids outside all the time and nothing seemed to be wrong.

"Last week I saw them playing,” she said. “It seemed like a normal happy family."