Forensic experts in Uruguay have unearthed remains of a person believed to be one of the victims of the military rule in the 1973-85.
The skull was found following an anonymous tip-off
A skull was found at army barracks near the capital Montevideo after officials were sent a hand-drawn map anonymously.
It was a second find in a week after recently-elected President Tabare Vazquez had ordered the excavations.
Some 180 Uruguayans are believed to have died during the military rule, most of them in neighbouring Argentina.
"The skull was in a pit about 80cm (32 in) deep and covered with a kind of gravel used in construction," presidential chief of staff Gonzalo Fernandez said at a news conference on Friday.
Mr Fernandez said it was found at the so-called Battalion 13 site, between a football field and a stream.
He said that the officials acted after the map was mailed anonymously to his office, adding that search would continue over the weekend.
On Tuesday, experts found a man's skeleton at a farm north of the capital.
Bill on debate
Until now there had been no official investigation in Uruguay into the military rule.
Correspondents say left-leaning Mr Vazquez has promised to change that. On taking office in March he ordered the armed forces to identify possible burial sites.
Mr Vazquez has pledged to reveal the full story of abuses committed by the military.
The finds came as the Uruguayan parliament started debating a bill that could allow more prosecutions.
At present an amnesty law protects military officers in Uruguay.