Officers were called to an apartment on Sunday evening to investigate reports of a fight, according to a department news release. They discovered a 28-year-old man had been stabbed several times. He was transported to Mercy Hospital; a doctor there described one of the man's wounds as near fatal. A 32-year-old pregnant woman and two children who were sleeping in the apartment at the time of the incident weren't hurt.
Another 28-year-old man in the apartment tried to flee. Officers arrested him after a short foot chase. He was taken to Mercy Hospital with an apparent ankle injury, the news release said. He was covered in blood and mud, the news release said, but the mud wasn't consistent with the apartment scene.
Investigators learned that before the stabbing the man had tried to set a parked vehicle on fire and stated he had killed three people that night and "we are all going to die."
He also said at some point before the fight that he was going to drink and do drugs with a woman under a bridge spanning the Rock River. Officers searching the area around the bridge early Monday morning discovered a dead woman behind a former furniture store. Authorities have not identified her yet.
Seventy-five-year-old Mary Coulthard was reported missing from her apartment on Saturday morning. Searchers found Coulthard's water bottle on another Rock River bridge south of the area where the dead woman was found. Police say they don't believe the dead woman is Coulthard, saying she appears to be significantly younger.
The man was being held at the Rock County jail Monday on suspicion of attempted homicide, attempted arson, criminal damage and disorderly conduct as detectives try to piece together his activities over the last three days.
Police Chief David Moore didn't immediately return messages from The Associated Press on Monday afternoon.
Janesville, a city of about 63,600 people, is about 45 miles south of Madison.