FORT WORTH It was a mystery for nearly a year.
A woman was raped in her own home on Little Mohican Drive in Fort Worth, in September 2012 during the overnight hours.
She survived the attack, but fear still stalked her.
'I can't even begin to imagine the terror and the fear you have to live with if you have no idea of who you fell victim to,' said Detective John Galloway of the Fort Worth Police Department Sex Crimes Unit.
The woman's sense of safety was stolen, but Galloway wanted to give it back to her.
'There is a certain level of frustration, because as part of being an officer or a detective, you want to protect,' he said.
When Galloway got the case, he only had the victim's words and a sketch, but he did have DNA evidence. He entered that information into a database and waited.
This summer, that evidence turned the sketch of the attacker into the face of Arturo Valtierra.
'I'm going to tell you that, in this case, that biological evidence was critical,' Galloway said. 'It's what helped us to get to the suspect.'
Valtierra was caught in El Paso in June, where he is accused of raping at least three women. Detectives said he was watching them before the attacks, burglarized their homes, and then returned to rape his victims.
'I believe that he would have certainly kept going if we wouldn't have been caught, and maybe even escalated,' the detective said.
Galloway has met with Valtierra. While the suspect showed no remorse, there's already plenty of satisfaction for the lawman who tracked him down.
'He was no longer a danger to her [or] to anybody else, so it was very exciting,' Galloway said.
He was finally able to give the woman on Little Mohican Drive some peace.
'She was very happy,' Galloway said. 'Very happy to find out she was safe.'
Fort Worth police only have one case against Valtierra, but the agency is reaching out to other police departments in North Texas to see if there may be other other victims.
Valtierra pleaded not guilty to the long list of charges he's facing in El Paso. He has yet to be indicted in Tarrant County, but prosecutors have filed their case.