SAN SALVADOR, El Salvador - El Salvador's congress has approved a temporary measure to allow about 1,000 old or sick inmates to leave prison, to free up police to fight gangs.

The legislation approved Wednesday may also help reduce overcrowding in the Central American country's prisons.

The government has said it is studying a series of measures to improve the fight against violent Mara street gangs.

The measure approved Wednesday will allow the release of inmates with a terminal or degenerative illness and prisoners over age 60 who have served at least a third of their sentences.

Nobody with a sentence of over eight years nor those convicted of serious offences will be eligible under the measure, which is scheduled to last one year.