(Reuters) – All US federal prisons were closed on Tuesday following a deadly gang war between several Texas inmates.

In an email statement, the Bureau of Prisons (BOP), stated that two prisoner died at Beaumont Prison, Texas. This is where violence broke out. Two additional prisoners were admitted to the hospital. However, no information was available about their health.

BOP claimed it had acted with an “abundance caution” by ordering the nationwide lockdown. It is rare that inmates are kept in cells.

In the United States, there are 130 federal prisons housing more than 134,000 inmates.

The BOP stated that it expected the security measures to be temporary. The BOP stated that it will monitor the events closely and adjust its operations as necessary to adapt to changing circumstances.

There were no additional details.

The New York Times, reporting unidentified sources said that members of MS-13 the violent Salvadoran streetgang were involved with fighting at Beaumont Prison. It stoked fear that violence might spread to other prisons because rival gang members wanted retribution.

BOP director Michael Carvajal announced this month that he will be retiring, but will remain in the position until another director is appointed. Carvajal was criticized for his leadership in the fight against coronavirus, and other issues.