Journalists Koos Koster, Jan Kuiper, Hans ter Laag and Joop Willemsen were filming a documentary on the conflict when they were killed in an ambush.

The defendants, now in their 80s and 90s, are former defense minister Jose Guillermo Garcia, former Treasury Police chief Francisco Moran and ex-infantry brigade commander Mario Adalberto Reyes Mena.

The court initially sentenced them to 15 years each in June but clarified Thursday that because four people were murdered, the total sentence for each man is 60 years.

However, they will serve only 30 years because this was the maximum allowed under the law in force at the time of the killings, the victims' lawyer Gustavo Huezo told reporters.

The court also ordered the Salvadoran state to publicly apologize to the families "for the delay in justice" and because the perpetrators belonged to the military high command.

President Nayib Bukele, as commander of the armed forces, must issue the apology within 30 business days.

The case was frozen in 1993, after the enactment of a law pardoning war crimes.

It was reopened in 2018 after the Supreme Court declared the amnesty law unconstitutional, but relatives of the victims still had to wait years for the main hearing.

El Salvador's civil war, which pitted the military against leftist guerrillas, left more than 75,000 people dead.

Garcia led the Armed Forces from 1979 to 1983, when the worst massacres perpetrated by the military took place.