MESA, Ariz. -- A man accused of stabbing two men in two days at a Phoenix-area shopping mall told investigators he did it because the victims disrespected him, according to police.

Bernard Allen, 25, was arrested Monday after security guards at Fiesta Mall in Mesa found a man dead in a bathroom near the food court.

Allen made an initial appearance Tuesday and was ordered held in lieu $500,000 bond. The public defender's office was appointed to represent him but no lawyer has yet been assigned.

Allen told police the victim, 31-year-old Issurah Jackson, had bumped into him on the way to the bathroom, according to a probable cause statement.

Allen said he was so enraged by Jackson's "disrespect" that he stabbed Jackson in the back as Jackson stood at a urinal, using an 8-inch butcher knife he had just bought for $41.60 at a store in the mall, the statement said.

Police said Allen calmly left the restroom. Witnesses called 911 and reported seeing a man walking slowly through the mall with a bloody knife, according to the statement.

Police arrived and arrested Allen outside the west entrance of the mall; officers said he was still holding the bloody knife.

The victim's mother, Mary Babbitt, said Tuesday she was devastated.

"I'm in shock," Babbitt said. "I just can't hold it; I can't hold myself together."

Jackson's family packed up his Tempe apartment Tuesday afternoon.

As they gathered, they remembered him as a loving, kind and smart man. They said he was a man devoted to his parents and family members.

"He's always wanted kids of his own," said his sister, Lynnette Nahlee. "He always used to say, 'You're so lucky you have a big family.'"

Jackson's accused killer told investigators he suffered from schizophrenia and blackouts. According to the probable cause statement, Allen said he couldn't remember parts of the stabbing because he had blacked out.

Police said Allen also admitted to another stabbing at the same mall the day before. In that incident, police said, 22-year-old Lathaniel Brown was stabbed in several times in the neck and shoulder.

Allen told police Brown walked past him in the mall and the two made eye contact, according to the statement.

Not liking the way Brown looked at him, Allen grabbed the other man from behind and stabbed him in the throat with a pocket knife, the statement says.

When Brown, who did not know Allen, asked what Allen's problem was, Allen replied, "You [expletive] disrespected me," and stabbed him three more times, according to the statement.

Brown ran away and Allen fled the scene, police said. Brown was transported to a hospital with non-life-threatening wounds.

Allen is an ex-convict who served seven years in prison for a drive-by shooting. He was released two years ago.

According to court documents, Allen was treated for unspecified mental health issues while on probation. During a probation hearing in June, a judge warned him to take medications as prescribed and noted that Allen has disagreed with doctors about his treatment.

On Oct. 17, Maricopa County probation officer Jan Johnston asked a judge to release Allen from probation, noting that he completed almost half of his three-year probation term without incident. Johnston also said that Allen is attending school and recently got a job.

A month later, on Nov. 19, Allen was released from probation.

He now faces charges of first-degree murder and aggravated assault.

The Mesa Police Department said it will be hosting a community meeting on Wednesday, April 2 at 6:30 p.m. at Rhodes Jr. High School at 1860 S. Longmore in Mesa to discuss the recent stabbing incidents. Criminal activity in and around the Fiesta Mall area will also be addressed.