A three-way sexual encounter led to violence, with a woman stabbing two men with a knife as they wrestled on the floor, Boulder authorities said.

The incident happened early Tuesday in a Murray Street home after two men returned from a local bar and had sex with a woman, the Sheriff’s Office said in a media release.

The woman, Serena Brooks, 30, of Niwot, has been arrested on suspicion of felony first-degree assault and misdemeanor child abuse, police said.

A 6-month-old child was home at the time of the incident, police said. The child was asleep and not injured.

Police identified the victims as 28-year-old Ruffin Griffin, Brooks’ husband; and Clint Cadigan, 27.

After being stabbed, the two men drove together early Tuesday to Boulder Community Hospital to be treated for their injuries. Hospital staff reported the stabbings to police.

Brooks also was injured in the incident. Details on her injuries were not available.

Police said Brooks used a knife in an attempt to break up the fight between the two men.

Drugs and alcohol played a role in the incident, police said. Details on why the two men began to fight were not released.

Kieran Nicholson: 303-954-1822 or knicholson@denverpost.com