York County sheriff’s deputies, officers from surrounding towns and ambulance crews responded Wednesday night to what they initially thought was a riot at the York County Jail in Alfred.

Sheriff William King Jr. said the situation was “mischaracterized as a riot.” He said about 30 inmates from the jail’s largest housing unit created a disturbance around 8:30 p.m., when the men became “passively non-compliant” over recent operational changes at the jail and refused to return to their cells.

That prompted the jail supervisor to call in all available personnel to monitor the situation, according to a statement from King. The main entrance to the jail was blocked for more than an hour by police cruisers.

King said the inmates were eventually persuaded to return to their cells. All inmates had been locked in their cells by 9:20 p.m.

The incident is under investigation, King said, and the inmates who are identified as instigators will face administrative sanctions.