Arthur Levan Williamson was charged in connection with the attack that ended with the slaying of Jim Nicolai, who went by the name Jim Matthews as a news anchor for WWJ radio, officials said.
Williamson was charged with seven criminal counts: first-degree murder, felony murder, two counts of assault with intent to murder and three counts of unlawful imprisonment.
Matthews was found dead at his Chesterfield Township residence on Bayview Drive around noon Friday, police said.
Macomb County prosecutors said the deadly encounter was a "hammer attack" in a statement but declined to clarify exactly how Matthews was killed.
"The only thing we have is blunt-force trauma, and we won't go into any more detail than that," Brian Bassett, the director of the Chesterfield Township Department of Public Safety, told reporters.
Williamson was arraigned Monday, and a lawyer representing him during the brief hearing declined to comment.
Three other victims who were at the home, including Matthews' two children, were hospitalized.
A 35-year-old woman, whom authorities identified Monday as Nichole Guertin, escaped with her 5-year-old daughter before she flagged down a driver and called 911.
Officers found the body of a man in the home, as well as a 10-year-old boy who was bound and in a closet.
The woman was identified as Matthews' girlfriend and the mother of his children, NBC affiliate WDIV reported.
The attacker had been let into the home sometime "in the middle of the night" before Matthews got home at about 6 a.m., Bassett said. Police were called to the scene at about noon.
“Between that, unfortunately, we don’t have a lot of the details," Bassett said. "He was welcomed in as a guest of the home.”
Bassett and Macomb County Prosecutor Peter Lucido urged residents to be vigilant against domestic violence.
“This is somebody who has been there in the past,” Bassett said. "Exactly what the nature of the relationship [was], we’re still trying to develop that."
It wasn't immediately clear how Williamson was known to the victims, other than that he "wasn't an un-welcomed guest," Lucido said.
"If I had an answer, I would give it to you," he said. "But unfortunately, at this time, the relationship that had been established, we know that it was not a breaking and entering. ... He was not an unwanted guest at the place."
Guertin and the 10-year-old were being treated at a hospital Monday while the youngest victim has been released, officials said.
The suspect was treated for a potential overdose when police arrived Friday, Bassett said.
Williamson was ordered held without bail. State corrections records show he has a long criminal record that includes prison stints for assault, kidnapping and illegal weapons possession.
Lucido summed up the state of the case as "limited clarity."
"You have to start to put the pieces together, which is not always easy," he said. "You're saying to yourself, was this a suicide of some sort? Was this a murder? What was it?"
This article was originally published on NBCNews.com