Severe overcrowding at Maui’s jail is likely what led to an uprising at the facility Monday afternoon that left three staff members with minor injuries, according to Nolan Espinda, director of the state Department of Public Safety.

Maui Community Correctional Center, like the other county jails, has been severely overcrowded for years, with inmates sleeping on the floors, a problem Espinda has highlighted throughout his time as public safety director.

He said there were 410 inmates being held at the facility at the time of Monday’s incident. The jail was designed to hold just 209 inmates but had been reconfigured to house 301 people.

Almost all of the inmates in at least one of the two modules involved were being housed four per cell, something DPS said was done only “on rare occasions when absolutely necessary.”

Ninety-five inmates from one of the modules have now been relocated to other spaces within the facility, further exacerbating the overcrowding, said Espinda.

“Conditions surrounding overcrowding create tense moments in the institution and problems,” he told reporters at the state Capitol on Tuesday. He said corrections officials have tried to increase recreational time to ease the tension.

The state has planned to relocate the jail from Wailuku to Puunene, spending close to $14 million on consultants and design and engineering services since 2011. As of 2016 the project appeared to have stalled, but officials said this week that it might move forward.

Just before 3 p.m. Monday, inmates from one of the jail’s modules were ordered back to their cells after being in the common area during recreational time. But 42 out of the 94 inmates refused, DPS said Tuesday in a news release. Inmates began breaking fire sprinklers, which began shooting water out into the common area. Maintenance workers were told to shut off the water, and some of the inmates started a small fire. The smoke drifted up into another module where inmates began another disturbance.

DPS said the damage to the two modules was “significant,” though estimates are pending.

At about 4:24 p.m., DPS said, staff and Maui police officers began negotiations with inmates in one of the modules, and the staff was able to gain entry into the area through an emergency exit door. Staff then turned their attention to the second module “that created a lesser disturbance,” and by 6:26 p.m. had “contained” the situation.

DPS said while no inmates were injured, three staff members who have since returned to duty were treated for “minor injuries including an injured finger, a cut to one foot from shattered glass and skin irritation from pepper spray exposure.”

The disturbance remains under investigation by both DPS and the Maui Police Department to determine how it started and why. “Once the inmates responsible for the incident are identified, they will be brought up on criminal charges as well as internal disciplinary action, pending the outcome of the investigations,” according to DPS.

Espinda said Tuesday that there could have been significant injuries if it wasn’t for the response from corrections staff and officials with the Maui Police and Fire departments.