Amnesty International charged the Chilean government of President Augusto Pinochet is blocking efforts to discover the fate of 700 political opponents who "disappeared" in the 1970s.

"If the Chilean authorities exercised the political will to uncover the full truth, hundreds of families would be released from the painful search for missing relatives," a report released Tuesday by the worldwide human rights group said.Amnesty said its 18-page study "compiles, for the first time, a summary of the massive amount of evidence that has emerged through the years about how and by whom `disappeared' prisoners were arrested and about the secret detention centers in which they were held."

The report uses the word "disappeared" in quotation marks to signify enforced or involuntary disappearance. The victims are not simply missing persons, Amnesty says. "Evidence indicates that they have been taken away by government agents in acts of political persecution."

Most of the 700 Chilean "disappeared" turned up missing after the 1973 military coup that brought Pinochet to power. The new regime enforced a crackdown on supporters of the previous president, Marxist Salvador Allende.

Similarly, thousands of people disappeared in neighboring Argentina during the so-called "Dirty War" between an Argentine military regime and left-wing guerrillas. But most of the cases there have been cleared up with the advent in 1983 of a democratic government and the discovery of mass graves.

Amnesty said the cases in Chile of nearly 700 "disappeared" prisoners have been sufficiently documented to have been presented to the courts.