The Salt Lake County Sheriff's office hopes the public can help track down a man who is suspected of assaulting his 86-year-old landlady in her Brickyard area home early Friday morning.

Ann Smart-Pearce was in surgery Friday afternoon at St. Mark's Hospital in "extremely critical condition," said Sheriff's Office Lt. Don Hutson.

Two other tenants were checking out a scuffle in the home just before 6 a.m., said Hutson, when they allegedly saw Arthel Martin assaulting the victim. They said they tried to prevent him from leaving the house, but Martin, 45, got into his dark green Hyundai Sonata with license plate Z216MN and fled from the home. He is 6 feet tall, 200 pounds and has an athletic build.

"He is not a person of interest," Hutson said. "He is a suspect."

Detectives spent much of the day on the scene, looking for evidence.

"The motive is unclear," Hutson said.

A search of state court records shows that Martin was charged in 2003 and 2007 for cohabitant abuse of two other women, both of whom had protective orders against him.

Smart-Pearce's grandson, Adam Maddocks, said his grandmother, a mother of four daughters, ran a photography business out of the home for many years with her husband. She is a frequent letter-to-the-editor writer and quite humorous, he said.

She had just returned home Monday from a weeks-long convalescence for a broken leg, Maddocks said.

"She's one of those grandmothers who's with it," he said. "I'm sure she fought" the attack.

Smart-Pearce has severe injuries to head and neck.

"If she does live, they say she will have brain damage," Maddocks said.

Sheena McFarland contributed to this report.