TAMPA, Fla. — The man the Hillsborough County Sheriff's Office charged with killing his girlfriend and her 10-year-old son says the incident started with an argument over watching football on television. 

• Woman, child found dead at apartment complex
• Hillsborough Co. Sheriff's Office: 42-year-old man arrested
• Tyrone Johnson charged with murder, child abuse

The victims were found dead Sunday evening at the Mariner's Cove Apartment complex at to 4302 Mariners Cove Court in Tampa. Officials have not released their identities.

Deputies came in contact with Tyrone Johnson just before 7 p.m. Sunday, as he was still on the scene when they arrived.

Monday morning, deputies announced the arrest of Johnson, 42. He faces charges of murder, aggravated child abuse and shooting inside of the apartment.

According to deputies, Johnson said the argument started after he change the channel on TV to watch football. 

The couple began arguing and Johnson went to a bedroom to gather his belongings and leave the apartment, according to what he told deputies.

According to the affidavit, Johnson said he has been using a knee roller to move around after surgery on his foot he injured while in the military. 

As the argument escalated, the girlfriend pushed him off his knee roller and he went to the ground, deputies said Johnson told them. Johnson also claimed the boy came into the room and accused Johnson of hitting his mother.

Johnson said he then pulled out a Glock 22 .40-caliber handgun and shot the girlfriend and her son. 

However, according to deputies, investigators found evidence inside the child's bedroom that there was gunfire in that room. They said they also found blood evidence underneath the child's bed.