PASADENA, Texas (KTRK) -- A man accused of fatally shooting his girlfriend overnight in Pasadena told police he mistook her for a burglar.

The family of the victim, Chrisheena Lee, is disputing his account of mistaken identity.

The shooting happened at an apartment at 4029 Burke Road near Fairmont shortly before 3:30 a.m. on Monday.

Pasadena police said Lee's boyfriend told them he heard a break-in at the door and grabbed his weapon.

Investigators said there is damage to the door of the apartment, though it is unclear if the damage is old or new.

"We're going to collect shell casings. We're going to look at the trajectory of the bullets and compare that to his statement and try to see if everything matches up. If it truly is accidental, obviously this is a very sad situation," Sgt. Raul Granados said. "If he did believe there was a break-in and, in fact, there wasn't, he ended up shooting his loved one. It's a very difficult situation for him. If there was an intruder, obviously, we want to find maybe doorbell cameras, maybe cameras at the apartment complex, to see if we are going to have to look for a suspect out there, or what happened at the door that startled him enough to get his weapon out and start shooting."

Police said the boyfriend stayed at the scene and is cooperating with investigators.

Lee's family, however, paints a very different picture.

"Unbelievable," Lee's mother said. She was too distraught to speak more about her daughter's death. However, her cousins wanted to speak up on Lee's behalf.

"She's been getting away from him. She's been telling the family he's stalking her," Lee's cousin, Tasha McCoy, said. "He just wouldn't leave her alone."

Family members invited ABC13 inside Lee's apartment, where they showed us the six bullet holes in the walls of the bathroom.

Relatives said in their opinion, the boyfriend made up the story about the intruder as a coverup.

"He should be in jail," another cousin, Travis McCoy, said. "You didn't have to go to this extent, and then you lie about it, and cover it up. It just doesn't make sense."

One thing not in dispute, is that Lee's boyfriend fired the shots.

Pasadena police recovered a weapon on the scene.

Lee's boyfriend was still held at the police headquarters on Monday. Investigators said he was under arrest on an outstanding warrant in an unrelated case. It was unclear what that case is about.

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