EPHRATA - A man reportedly killed Carmelita Lopez Santos because she wanted to end their relationship.

Grant County sheriff's deputies arrested Jose A. Aguilar Aguilar, 35, of Desert Aire, Monday night. He was booked into the Grant County Jail for first-degree murder, alien in possession of a firearm, harassment and intimidating a witness.

Investigators spent about two weeks tracking the man, while he reportedly used the victim's cellphone to talk to her family and friends, according to a Grant County sheriff's report.

Lopez Santos' body was discovered by a hunter near the Buckshot Wildlife Access Area near Mattawa on Oct. 16, according to the police report. The hunter's dog picked up a scent and followed a trail into the brush and the hunter noticed the body.

Officers discovered four 9mm shell casings and a bullet jacket near the body, according to the police report.

Lopez Santos reportedly went missing from Yakima on Oct. 15, after telling family members she was going to the Tri-Cities with a friend, according to the police report. When her brother called Lopez Santos, Aguilar Aguilar reportedly answered, telling her brother he got a call from another man accusing him of dating his girlfriend.

The phone call was the first in a series family and friends placed to Lopez Santos' phone, according to the police report. Most of the time Aguilar Aguilar reportedly responded he didn't know Lopez Santos and found the phone in a Walmart parking lot. He reportedly later added a friend called the phone and told him she went to Mexico.

At one point, Aguilar Aguilar reportedly threatened one of Lopez Santos' coworkers, saying he was Lopez Santos' boyfriend and "if they don't mind their own business he would come and shoot them," according to the police report.

Lopez Santos' brother identified the man as the same one who called his phone at all hours looking for Lopez Santos, after he let his sister borrow his phone, according to the police report.

"(Lopez Santos' brother) stated he did not know if this was related, but at the end of June his vehicle was 'fire bombed' and was completely burned to the ground," according to the police report.

"(He) also explained that a few weeks after that someone broke into his locked mail box; however, no one else's mail box had been tampered with. (He) told us he does not have any enemies and was unsure why these things were happening to him."

An unknown man also called Lopez Santos' fiance saying he wanted to fight over Carmelita. He threatened to "shoot it out" at a Yakima gas station or meet under the bridge near the river, according to the police report.

A neighbor reportedly saw Lopez Santos leave with Aguilar Aguilar at separate times, according to the police report.

Officers tracked Lopez Santos' cellphone and Aguilar Aguilar's Nissan Pathfinder to a home in Desert Aire, according to the police report. When officers contacted Aguilar Aguilar near a Mattawa laundromat, they discovered the Lopez Santos' cellphone in the vehicle.

When police questioned Aguilar Aguilar's roommates, one of them reportedly said Aguilar Aguilar confessed, showing him a newspaper article about the woman, and describing taking her out and shooting her, according to the police report.

Later in the night, Aguilar Aguilar reportedly drove them to a remote area in Grant County and threw items into a small canal.

"Afterwards Aguilar stuck a gun into (his roommate's) stomach and stated, 'I didn't make a mistake telling you I killed her, did I?'" according to the police report.

Aguilar Aguilar initially denied the murder, but after questioning reportedly confessed to killing the woman because she wanted to break up with him, according to the police report. Investigators allegedly discovered a 9mm handgun in Aguilar Aguilar's bedroom, and cowboy boots and a purse, both with blood stains.

"The black purse recovered matches the description of the purse Carmelita was seen leaving with and never recovered at the time of her body's discovery," according to the police report.

"Near the purse was a small photo of Carmelita."