Updated

Costa Rica's attorney general says an investigation of the 1984 bombing that killed three journalists and four Nicaraguan rebels at a news conference has been closed after officials determined the only suspect has been dead for decades.

Attorney General Jorge Chavarria says DNA tests verified suspect Roberto Vidal Gallini's identity and also showed he has been dead since 1989.

Two Costa Rican cameramen, four Nicaraguan rebels and U.S. journalist Linda Frazier were killed and more than 20 people were wounded in the blast at the village of La Penca, near Costa Rica's border with Nicaragua.

Costa Rican authorities said at the time that they suspected the bomb was planted by a man who posed as a journalist in a failed attempt to kill Contra rebel leader Eden Pastora.