LOS ANGELES (KABC) — Seven inmates were hospitalized Tuesday morning after a possible overdose incident at the Men’s Central Jail near downtown Los Angeles, officials said.

Shortly before 7 a.m., Los Angeles Fire Department fire-paramedics were called by LA County Sheriff’s Department personnel to “assist seven individuals (all believed to be in possession) who may have inhaled or were exposed to a substance that has not yet been formally identified in a prison,” the LAFD said in a statement.

All seven patients were transported to hospitals for further evaluation or necessary care, officials said. One is in critical condition and the other six were listed in serious condition.

“No growing or off-site hazards were identified,” the press release said.

DEVELOPMENT: More details will be added to this report as they become available.