RENO, Nev. (AP) — Federal agents have charged a 33-year-old man with murder in the fatal stabbing of his pregnant girlfriend in a brutal attack witnessed by her children on the Pyramid Lake tribal reservation north of Reno.

Michael Joshua Burciaga was being held without bail Thursday in the Washoe County Jail on one count of second-degree murder within Indian Country.

He’s accused of stabbing his girlfriend multiple times with multiple knives just after midnight Tuesday at her home in Nixon, where prosecutors say he returned while tribal police were investigating and confessed to the killing.

The victim was identified only by her initials, A.D., in a criminal complaint filed later that day in U.S. District Court in Reno. She was a member of the Pyramid Lake Paiute Tribe.

FBI Special Agent Adam Hawkins said in an affidavit attached to the complaint that Burciaga had slit his wrist and left a trail of blood on three different streets near the home before he returned and told Pyramid Lake tribal police officers what happened.

“I already know what happened, and I know what I did, which is why I slit my wrist,” Burciaga told the officers, according to the affidavit.

The affidavit said Burciaga told the officers while he was being transported to a Reno hospital in an ambulance that the victim was pregnant with his child and asked multiple times about her condition.

Federal court records don’t list a lawyer for him.

The victim’s daughter, one of three children at the home at the time, called police to report that her mother’s boyfriend had stabbed her, Hawkins said in the affidavit.

The girl told tribal police later that her younger brother woke her up and told her Burciaga had stabbed their mother. The mother was still alive and told the children to come into the master bedroom where she barricaded the door with a dresser, the affidavit said.

Burciaga broke through the top of the door and after the mother began striking his hand with a bat, was able to enter the bedroom and drag her into the master bathroom where he started stabbing her again, Hawkins wrote.

One child grabbed a lamp and hit Burciaga with it but was unable to stop the attack. Burciaga then went toward the kitchen, returned with a smaller knife and began stabbing the victim again, the affidavit said. She was pronounced dead shortly after the tribal police arrived about 12:28 a.m.