A man on parole for trying to infect children with HIV nearly 20 years ago pulled a boy into a Portland restaurant bathroom over the weekend, attempted to sexually assault him and then stabbed him several times, police said.

The 10-year-old's injuries from the attack Sunday were severe enough to require surgery, and officers said he would have died without immediate care.

The suspect, Adam Lee Brown, pleaded not guilty Monday in Multnomah County Circuit Court to charges that included kidnapping, attempted murder and assault. He appeared in court surrounded by sheriff's deputies and wearing a so-called "suicide smock," a rip-resistant vest that prevents inmates from tearing off strips of clothing with which to hang themselves.

His arrest Sunday after a two-hour standoff in which he was holed up in a Wendy's bathroom marks the second set of child sex abuse charges leveled against Brown, who was the subject of an abuse investigation two decades ago.

The HIV-positive son of a church pastor, Brown was convicted in 1993 of three counts of first-degree sodomy, each involving a child. He pleaded no contest to reduced charges — the initial charges included attempted murder because of his HIV.

The case came during a peak in the AIDS crisis and amid fears fueled by public misunderstanding that vengeful patients willfully would infect unsuspecting bystanders.

At least nine children in the small logging town of Roseburg told police that Brown molested them over the course of several months in 1992.

According to a criminal complaint, the children said Brown told them not to tell and threatened them with knives, scissors and matches. One child said Brown once burned a Bible, warning that Satan would come if they didn't do what he wanted.

Brown's wife at the time, Nancy, told The Associated Press in 1993 that her husband had contracted the disease in Southern California while he was stationed there with the U.S. Marines. A lay preacher at Fair Oaks Community Church, Brown served nine years in the Marines as a computer technician before his discharge in the early 1990s.

"God was always in the picture," Nancy Brown said about her husband's religious upbringing. "But he thought Satan would deliver the boys."

Brown spent 11 years in Oregon's prison system, accruing three years of earned time off a 15-year sentence. Prison officials said their records show Brown spent the years 1999-2004 without incurring any disciplinary infractions. Older, paper records were unavailable.

On Sunday, police said he pulled the 10-year-old boy into the fast-food restaurant bathroom and locked the door. After the boy fought back, Portland police say Brown stabbed him.

A Wendy's employee opened the locked door and Brown shoved the 10-year-old out of the bathroom but locked himself inside and told arriving officers that he had a gun.

Police evacuated the restaurant and brought in crisis negotiators. Brown surrendered. Police found a knife, but no gun.

Brown's parents could not be reached Monday by the AP.

An attorney representing Brown at the arraignment was unavailable for comment after the hearing. He declined to give his name.