Four people were hospitalized after a “physical altercation” Monday night at the Prince George’s County jail.

Andrew Cephas, public information officer for the county’s Department of Corrections, confirmed Tuesday morning that the injuries of the four people hospitalized are not life threatening. The four patients have since been returned to the Department of Corrections. Two of them were treated for “what appeared to be puncture wounds,” according to Cephas, and the other two were treated for minor injuries.

The altercation, which occurred around 6:20 p.m., involved six people, all of whom Cephas said are inmates. The two who were not taken to the hospital were uninjured and were taken to a maximum security housing unit. On Monday night The Washington Post reported that six people were stabbed at the jail, citing county police, but the local police department directed DCist/WAMU to Cephas on Tuesday morning for inquiries. He did not immediately confirm that the incident was a stabbing.

Investigation into the incident is ongoing. Cephas says the Department of Corrections’ Office of Professional Responsibility and Legal Affairs is working with the Prince George’s County Police Department to investigate.

This appears to be the second stabbing in the Prince George’s County Jail this year. In June, an inmate at the county jail died after another inmate stabbed him, investigators said.

Cephas also confirmed that the incident this week was not related to a temporary suspension of evening visitations at the jail announced Monday morning. The suspension is in place until Saturday, Dec. 17, due to renovations taking place in the reception area of the jail during the evenings throughout the week. The public still has access to the commissioner’s office.

This story will be updated as more information becomes available.