Five inmates at Two Rivers Correctional Institution in Umatilla died between Jan. 14 and 18 after testing positive for the coronavirus, according to the Oregon Department of Corrections.

That brings the total number of COVID-related prison deaths statewide to 33. The five men who died were all 55 years of age or older.

To date, 639 inmates at Two Rivers have tested positive for the virus and 304 cases are active, making the prison the center of the largest COVID outbreak in the state, based on data from the Oregon Health Authority. (There were 1,683 inmates at Two Rivers as of Dec. 1, 2020.)

So far, more than 3,000 inmates—or almost a quarter of the state's total adult prison population—have tested positive for the virus, as well as over 750 DOC employees.

"What we do know presently is mask wearing wasn't happening. Social distancing can't happen," says Juan Chavez, a lawyer who represents Oregon prisoners. "That combo will lead to this kind of mass casualty."