Salvadoran prison authorities confirmed Sunday that at least four inmates in the Quezaltepeque prison in San Salvador, were murdered on the weekend in a fight among the prisoners.

The assistant director of the country's prison administration, or DGCP, Nelson Rauda, confirmed to Efe that on Saturday night guards found "the corpses of three inmates in Sector 1 of the Quezaltepeque prison" and that on Sunday "another (body) turned up in Sector 2" in the same prison.

The victims were identified as: Jose Rodolfo Martinez Pineda, 19; Cesar Francisco Perez Garcia, 22; Juan Carlos Moreno Flores, 25 and Cesar Jonatan Ceron Enrique, 21, according to prison authorities.

The DGCP official said that all the bodies had "wounds from knives and blows."

Rauda said that the multiple killings came amid an "internal cleansing of the 18 gang," given that Quezaltepeque houses exclusively members of that group.

Interned in the prison, which is located in central La Libertad province, are 1,000 members of the Mara 18 gang, according to prison data.

Rauda said that authorities had decided to declare a "state of emergency" in the prison, with the measure consisting of suspending visits to inmates and increasing security measures, but he did not specify the duration of the decree.

This is the second such deadly incident to occur in a Salvadoran prison so far this year. In October, three inmates were killed in the prison at Ciudad Barrios, in the eastern province of San Miguel, Rauda said.

Meanwhile, San Salvador Archbishop Jose Luis Escobar Alas, during the traditional press conference after Sunday Mass, called the situation in the country's prisons, especially Quezaltepeque, "worrying."

He emphasized that the Salvadoran state has the obligation to guarantee the rights of the prison population, even though those people are in custody for breaking the law.

"It's true that they are deprived of liberty, but not the rest of their rights," he said, adding that "if the required attention is not given to them" the prisons could become "a type of time bomb, which is a threat for everyone."

The prelate said that it is "necessary" for the authorities to find "other civilized ways of guaranteeing the functioning of the prisons," adding that to do that it is urgent for prison overcrowding to be brought to an end.

El Salvador's prisons currently house more than 24,000 people, meaning that they contain almost three times the 8,300 inmates they were designed to hold.