Investigators say a 16-year-old girl who was found dead after a Monday night car crash in Waterbury, Connecticut, was shot moments before the accident by her uncle, who was driving the car.

After giving two false stories about how his niece, 16-year-old Evalyce Santiago, died, Dominique Pittman, 27, said that he accidentally shot her after the two got into a fight over their secret sexual relationship.

The warehouse worker was driving when he says Santiago threatened to expose their relationship to his wife, who is Santiago's aunt and adopted sister. Pittman and his wife have three kids together and the rest of the family was unaware about the affair.

At one point, Pittman says the fight escalated, with Santiago reaching into the center console to grab a handgun he had stored inside.

He says the two began to fight over the gun, and eventually he shot Santiago three times - twice in the head and once in the hand.

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Dominique Pittman, 27 (left, in court on Wednesday), says he fatally shot his girlfriend, 16-year-old Evalyce Santiago, in the head Monday night when she threatened to expose their relationship

Pittman was secretly dating Santiago while married to her aunt and adopted sister, who he has three kids with, police say

Pittman says he accidentally shot Santiago Monday night, and then crashed the car he was driving in Waterbury, Connecticut

Pittman sustained minor injuries. Santiago was pulled from the vehicle and pronounced dead

It was at that moment that he veered off the road and crashed the car - wrapping it around a telephone pole.

When police arrived at the scene around 8.30pm, they found Pittman outside the car wit minor injuries. They pulled Santiago from the burning vehicle, and pronounced her dead at the scene.

At first, police say Pittman told them that Santiago's boyfriend, who's name he doesn't know, was in the car. He said that the man shot her and then fled the vehicle.

He later changed his story again, saying that Santiago was accidentally shot after the two got into a fight when she demanded that he loan her money to buy a winter coat.

Pittman eventually copped to being in a relationship with Santiago when police confronted him about the possibility of Santiago being pregnant and finding traces of his DNA, NBC New York reports.

According to court documents, Pittman said he 'last had sex with her around the beginning of November.' Investigators are still determining how long the relationship had been going on for.

Family and friends said they had no idea that Pittman was having an affair with Santiago (left and right)

Pittman appeared in court on Wednesday, when he was officially arraigned on murder charges. He was also hit with weapons charges including carrying a pistol without a permit and weapons in a motor vehicle, murder.

Pittman's bail was initially set at $1million, but raised to $3million on Wednesday when the motivations behind the murder were revealed.

He is due back in court on December 20.

Family and friends were shocked after hearing about the affair in court on Wednesday. At one point, a fight broke out outside of the court house.

Pittman appeared in court on Wednesday when he was charged with murder and his bail was raised to $3million

'He was my son in law. I just want the truth,' Francisco Rivera, the grandfather and adoptive father who raised Santiago said. 'He was dating my daughter and he has three kids with my other daughter.'

'Nobody knows nothing until something happens. That's when we all realize the tragedy. It was under our noses and we didn't see it,' he added to NBC Connecticut.

'I don't believe it. I know his girlfriend and that's not the girlfriend,' Rosara Rodriguez told WFSB. 'His girlfriend's of age and they're all family he's not going to do something crazy like that.'

One of Santiago's friends, Davionna Copeland, said that the teen had recently talked about her uncle and said nothing ever happened between them.

'She was venting to us literally before she died she told us I trust him that's my Uncle I don't think he would do anything,' Copeland said. 'That's really who I grew up with. She said we never did anything it was an incident one time but she still trusted him after the incident.'

'He didn’t do it,' said James Murphy, Pittman’s co-worker told Fox 61. 'He doesn’t get in trouble. He doesn’t really bother anybody. It doesn’t make sense.'