Enraged that his girlfriend walked out on him with their child, a Hoffman Estates man fatally stabbed the woman's father, sister and grandmother and critically injured her mother during a bloody attack outlined by prosecutors Saturday.

Cook County Circuit Judge Samuel Betar ordered D'Andre Howard, 20, held without bail following the hearing in Rolling Meadows on what prosecutors said is a potential death penalty case.

The episode began, prosecutors said, when Howard and his girlfriend, Amanda Engelhardt, 23, got into a heated argument Thursday night over Howard's alleged infidelities. Engelhardt left the apartment with their 8-month-old and went to her family's home a few blocks away.

Most of the eight people there were sleeping when Howard showed up at 1:30 a.m. Friday, prosecutors said. Soon the couple began arguing again-waking those sleeping above the first-floor family room.

Concerned about the noise, mother Shelly Engelhardt, 53, crept downstairs with her 18-year-old honor student daughter, Laura Engelhardt. As the two approached the family room, Howard confronted them with a butcher knife he'd taken from the kitchen, prosecutors said. He threatened all three women before tying them up with yarn as they sat on a couch, authorities added.

A few minutes later Amanda Engelhardt's aunt-whom authorities did not identify-came downstairs. After telling the aunt to join the others on the couch, Howard inexplicably decided to untie them, prosecutors said. He set down the knife and untied Laura Engelhardt first. Prosecutors said as Howard untied his girlfriend, her sister Laura decided to defend her family.

Prosecutors laid out a quick chain of events: Laura Engelhardt grabbed the knife and slashed Howard's arm, but he got it back and stabbed her several times. As she lay bleeding, Howard critically wounded Shelly Engelhardt, stabbing her in the heart and lungs. Next, Howard found grandmother Marlene Gacek, 73, in the kitchen and fatally stabbed her in the chest as she tried to get away. Howard then killed the father, Alan Engelhardt, 57, slashing his throat before he collapsed in the family room near his seriously injured wife and daughter, prosecutors said.

Howard returned to the family room, where his girlfriend, who was not injured, convinced him to let her call police. When officers arrived about 6 a.m., they found Alan Engelhardt and Gacek dead and Laura Engelhardt critically wounded, police said. Before she died about noon Friday in a hospital, she identified Howard as the attacker, police said.

On Saturday, Jeff Engelhardt, 20, a junior at Southern Illinois University, said his mother, Shelly, remained hospitalized and was conscious but not talking much.

Steve Herczeg, an assistant public defender, said Howard suffers mental health problems, has a history of juvenile delinquency and was convicted of aggravated criminal sexual abuse as a juvenile in 2004.

"He seemed pretty normal," Jeff Engelhardt said of Howard. "There would be arguments, but there didn't seem to be any indication that a violent incident could take place."