A Portland man on Friday pleaded not guilty to rape and strangulation charges, and authorities are asking for help determining whether there are other potential victims.

Rafael Gustavo Alcon-Ayala, 30, is accused of raping three people and strangling one of them in 2016, 2017 and 2019 incidents.

He was booked into the Multnomah County Detention Center on Thursday and pleaded not guilty to five counts of first-degree rape and one count of strangulation Friday.

Authorities ask anyone who has information about Alcon-Ayala to contact Portland police Detective Michael Greenlee at 503-823-0871 or Michael.Greenlee@portlandoregon.gov.

-- Jim Ryan; jryan@oregonian.com; 503-221-8005; @Jimryan015

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