Recently declassified U.S. documents reveal that Argentine dictatorship agents in 1976 dynamited the bodies of 30 people who had been detained in a blast that spread their remains over a wide radius.

The 10 women and 20 men had been detained and executed in the Argentine town of Pilar. The grisly details about the Aug. 20 explosion were found in a recently declassified Central Intelligence report posted Thursday by the independent National Security Archive.

The documents are a small selection of The Argentina Declassification Project - the largest government-to-government declassification effort in U.S. history.

The National Security Archive says they "provide a riveting account of the Argentine military's killing machine..."

Human rights groups estimate about 30,000 people were killed or forcibly disappeared during Argentina's 1976-1983 dictatorship.