Several clinical and corrections staff members at the Sherburne County jail went to hospitals after some of them reported feeling ill while dealing with an inmate having a “medical emergency,” the sheriff said Thursday.

Eight of the people were taken from the facility in Elk River to Allina Health’s Mercy Hospital in Coon Rapids, said Allina spokeswoman Terri Dresen. One of them, the inmate, remained hospitalized late Thursday afternoon in stable condition, said Sheriff Joel Brott.

Four others went to St. Cloud Hospital for treatment, according to emergency dispatch audio.

There they were treated without requiring hospitalization.

Brott has not disclosed the nature of the inmate’s medical emergency, but added that he “was not under the influence of illegal substances.”

Brott said that one or more of the contracted clinical staff “reported feeling tingly in their fingertips,” and corrections personnel were also checked out “as a precaution ... not knowing the reason for the medical emergency.”

A thorough search of the inmate’s cell revealed nothing unusual or suspicious, Brott said.

Brott said he is confident that his office’s investigation will determine what was behind the incident.

The sheriff did not identify the inmate involved but disclosed that he was under U.S. Marshals Service custody.