BOGOTA (AFP) – A fire at a prison in Colombia killed nine inmates and left 25 injured, the head of the country’s penitentiary system said Tuesday.

The blaze broke out Monday night at a prison in the northern city of Barranquilla, said the official, Saul Torres.

He said four prisoners died of the burns at a hospital and the other five fatalities remained inside the prison.

Early indications are the blaze started when inmates set fire to mattresses during a fight.

Anxious relatives crowded outside the gates of the facility, built to house 400 prisoners but home to some 1,200.