TIPTON, Mo. (AP) — A mid-Missouri prison is on modified lockdown after some upset inmates caused a disturbance in housing units overnight, a corrections official said Thursday.

No one was injured in the disturbance at the Tipton Correction Center, said Missouri Department of Corrections spokeswoman Karen Pojmann.

The incident began between 9 p.m. and 10 p.m. Wednesday when some inmates refused to return to their housing units after recreation time and had to be escorted by officers, Pojmann said. Further confrontations were reported in three housing units but major damage, such as broken windows and damaged walls, was reported in only one unit.

Special response teams from the prison and nearby jurisdictions were brought in and the situation was under control by 5:30 a.m. Thursday, she said.

Pojmann said inmates apparently were upset over rules regulating such things as how many inmates can congregate in one place. She said the rules were already in place but had recently been more strictly enforced at the correctional center.

It's unclear how many inmates were involved because they covered security cameras in the units, according to the spokeswoman.

All visiting hours at the center have been canceled for the weekend.

Gary Gross, director of the Missouri Corrections Officers Association, said the incident was part of a broader trend in the state.

"There is a lot of prison unrest all around the state, and a tremendous shortage of staff to keep 'em under control," he said.

The correctional center in Tipton, about 110 miles (177 kilometers) southeast of Kansas City, is a minimum security-center with a capacity of about 1,200 male inmates.