Prosecutors filed second-degree murder charges Thursday in the death of a 31-year-old Inver Grove Heights woman, in a sexual assault case that Ramsey County Attorney Susan Gaertner said left her "sickened and horrified."

The Ramsey County Attorney's Office filed charges against 31-year-old Michael Sontoya of St. Paul, who allegedly sexually assaulted Gabriela Romo, resulting in her death, in the early morning on Tuesday, in Sontoya's West Side duplex.

"This case is unique in the savagery of the sexual assault," Gaertner said. "I have been prosecuting rape cases for over two decades, and I have never seen anything like this."

Sontoya pleaded not guilty at a hearing Thursday; bail was set at $250,000.

According to the charges:

Sontoya and Romo, who knew each other, got drunk at Fabulous Fern's Bar and Grill in the Cathedral Hill neighborhood. They left the bar between 1:30 and 2 a.m. and returned to Sontoya's house.

Sontoya told police that after they had consensual sex, there was blood everywhere and he wiped down some of the walls, which had bloody handprints on them.

When police arrived at 7 a.m., after Sontoya had called to report finding Romo unconscious, they came upon a gruesome scene. Romo was lying on her back on the carpet, almost naked.

The police saw dried blood under her fingernails, and in her navel, but her stomach and hands had been wiped clean.

There was also blood spattering and smears on the walls, which Sontoya had tried to wipe clean, and what police said appeared to be "a piece of human flesh on the floor."

According to the Ramsey County Medical Examiner, Romo, a mother of four, bled to death from internal injuries caused by a sexual assault.

Defense attorney Anthony Torres said Sontoya and Romo had known each other since second grade, growing up together on St. Paul's West Side. They did not have a previous romantic relationship, he said.

Torres said the allegations are "probably not going to be justified" and the inference that an assault had happened will "be strongly tested."

According to Torres, Sontoya is a youth football coach and has had the same employer for five years. Torres has defended him the past, and said that he was surprised to hear the police allegations because "this would not be consistent with the person that I know."

According to court records, Sontoya has been arrested in the past for domestic assault, as well as twice for assault with a dangerous weapon, but the domestic assault charges were dropped and he was acquitted of the other assault charges. Emily Johns • 651-298-1541