OREM — Police say a man who attacked random breakfast customers with scissors in Orem before he was shot by an off-duty Chicago police officer showed no homicidal or suicidal tendencies two days before the attack.

Salt Lake City police officers had been called to conduct a welfare check on Sergio Walter Weffer, 33, at his mother's home on Thursday, because his mother was concerned about him.

"He was mentally ill and off his medications, according to his mother," said Lara Jones with Salt Lake City police.

Mental illness may explain Weffer's behavior Saturday morning at 8 a.m., when police say he began stabbing a 28-year-old Boise man.

"We don't know what he is diagnosed with officially, but we do know there are some serious psychological problems," said Orem Police Lt. Doug Edwards.

The man was saying goodbye to his Provo girlfriend at IHOP at 850 W. University Parkway when they were approached by Weffer, whom neither of them knew.

The approach startled the couple, and Weffer told them "I'm sorry," then proceeded to stab the man with scissors in the face, neck and arm, police said.

During the stabbing, the victim fell to the ground and Weffer fell on top of him, police said.

The off-duty Chicago officer, who was in Utah for training, was waiting at the door for a fellow officer and rushed over when he saw the attack.

The officer first thought the scissors was a knife and drew his gun, ordering the man to drop his weapon, Edwards said.

Instead, Weffer made another motion as if he was going to stab the victim, and the officer shot the man in the back, Edwards said.

Weffer fell off the stabbing victim and was restrained by the Chicago officer until Orem officers arrived, Edwards said.

The victim was taken to Timpanogos Regional Medical Center but has since been released and is back in Boise, Edwards said.

The Chicago officer was not injured and is back in Illinois.

Weffer is still in Utah Valley Regional Medical Center in fair condition. He may remain there for several days before being booked into jail.

Edwards said they later found Weffer's car parked down the road with two flat tires from punctures that he may have made.

E-mail: [email protected]