SEATTLE — A violent sex offender who recently fled Canada is now suspected of sexually assaulting a 16-year-old boy in Seattle just days after arriving in the city, police said Tuesday.

Michael Sean Stanley met the boy at a west Seattle grocery store, struck up a conversation and walked with him to an alley where he plied the teen with alcohol, Seattle police said in a statement. Stanley grabbed the teen and sexually assaulted him, police said.

The boy pulled a knife and was able to run away and contact police.

Detectives believe the incident happened before police received several calls reporting noise in an alley and Stanley threatening someone who asked him to be quiet.

When police arrived, Stanley became combative and said he had a knife. He appeared intoxicated, according to authorities. He was arrested and jailed for investigation of harassment, although police were working to rebook him on additional charges Tuesday afternoon.

Stanley was released from jail in Canada in April 2011 after completing a 32-month sentence for assault and forcible confinement.

He was being monitored by police under a peace bond, which Canadian authorities can get to impose conditions on individuals in the community. Stanley’s peace bond has 20 conditions, including one ordering him to stay away from children.

Police in Canada issued a public alert earlier this month after Stanley cut off his electronic-monitoring bracelet. Officials described him as an untreated, violent offender who posed a significant risk.

An American citizen, Stanley crossed the border and was located in the Seattle area last week. Canadian officials decided not to seek extradition.

He registered as a sex offender with the King County sheriff’s office and listed his address as an intersection just a block away from Pike Place Market, a scenic destination for tourists and locals.

It’s also near a preschool, even though he had been ordered to stay away from children in Canada.

Ilene Stark, executive director at Pike Market Child Care and Preschool, said the community felt threatened by Stanley’s arrival in the area, given that his recent history made him seem like a dangerous and unpredictable person. The preschool reviewed its lockdown plan, kept in constant contact with security in the area, and provided images and descriptions of Stanley to teachers and parents.

“It’s been intense,” Stark said. “It felt like there was a threat in our community and that we needed to be much more vigilant – more than in everyday life. It was disconcerting.”

Stark said she was saddened that something horrible apparently had to happen before Stark was collected by U.S. law enforcement. At the same time, she said her sadness was coupled with relief knowing that there is more legal control over Stanley’s whereabouts.

Before Tuesday, there was no reason to arrest Stanley since Canada hadn’t pursued an extraditable warrant and he wasn’t wanted for any crimes in the United States, authorities said.

Edmonton, Alberta, police spokesman Chad Orydzuk said when Stanley breached the monitoring conditions in Edmonton, officials searched for him and notified the public and other agencies.

Unconfirmed sightings of Stanley led schools in several west-central Saskatchewan communities to lock their doors and keep children inside.