NEW MEXICO – When police were called on Wednesday to an apartment complex in Albuquerque, New Mexico, they thought they were responding to a battery call.

Instead, they found 10-year-old Victoria Martens. She had been killed hours before her 10th birthday party.

The girl’s mother, Michelle Martens, 35; Martens’s boyfriend, Fabian Gonzales, 31; and Gonzales’s cousin, Jessica Kelley, 31, have been charged in connection with her death.

“This homicide is the most gruesome act of evil I have ever seen in my career,” Albuquerque Police Chief Gorden Eden Jr. said in a statement. “A complete disregard of human life and betrayal by a mother.”

Police said the girl had been drugged with methamphetamine, sexually assaulted and stabbed. Her body was dismembered in an attempt to hide the evidence. All three adults were believed to have been present during her murder. 

The girl’s mother originally told police after they arrived that “someone killed her daughter” and that the woman who did it was still inside the second-floor apartment.

The boyfriend, who was wearing bloodstained shorts, told police that he was “cleaning” himself up before officers got there, according to the complaint.

Meanwhile, the fire alarm inside the apartment went off. Officers went inside the smoke-filled unit to try to look for the child, the complaint said, and found her body in the bathroom. 

They also found bloodstains on the carpet of the girl’s bedroom.

Martens, Gonzales and Kelley are facing several charges, including child abuse resulting in death, kidnapping, tampering with evidence and conspiracy, according to online jail records.

Gonzales also is charged with criminal sexual penetration of a minor.

Gonzales denied any involvement in the child’s death and pinned the alleged crimes on his girlfriend’s cousin.

“Jessica Kelley did it,” he told reporters as he was being arrested Thursday morning.

“Not the whole truth,” Tixier said, “but it’s not a lie.”

Martens, who has a cut between her eyes, was followed by reporters as she was being arrested. 

Tixier said she showed no remorse when talking to detectives, the Albuquerque Journal reported.

“This is a horrific tragedy for our community. When something like this happens to our community, it has an effect on each and every one of us,” Eden, the police chief, said at a news conference Wednesday afternoon. “I want to assure the public that we will pursue justice, and we will make sure that we exhaust every resource into this investigation.”

He said there are no other suspects in the case.

Methamphetamine, much of it provided by Mexican drug-trafficking organizations, is the foremost drug threat in New Mexico, according to a 2011 report by the Justice Department.

Methamphetamine represented about 25 percent of all drug reports in Albuquerque during the first half of 2013, according to a 2014 report by the National Institute on Drug Abuse. That’s a higher number than for drug reports involving cocaine and heroin and a bit lower than marijuana reports.

In a statement, New Mexico Gov. Susana Martinez (R) called the manner in which Victoria was killed “atrocious.”

“What happened to this little girl is unspeakable,” she said, according to media reports, “and justice should come down like a hammer on the monster who committed this murder.”