An internal FBI report concludes that the bureau's investigation of opponents of Reagan administration policies in Central America was too broad, government sources familiar with the review said Friday.

The report said the anti-terrorism guidelines the bureau used to conduct the probe from 1983 to 1985 allowed the FBI to launch a widespread investigation and that those guidelines should be tightened up, said the sources, speaking on condition of anonymity.The tenor of one of the recommendations was that "the guidelines need to be made more specific to keep us out of trouble," said one source.

Another source said the report is "highly critical" of some aspects of the FBI's probe of the anti-administration Committee in Solidarity with the People of El Salvador.

It could not be determined whether the report, written by D. Caroll Toohey and Danny Coulson of the FBI's office of inspections, took top bureau officials to task for their handling of the CISPES investigation.

But the tone of the report "is pretty tough, these guys went way out on a limb; some top people at the bureau are saying `wait a minute, wait a minute,"' said another source familiar with the document.

The report, which is classified, was submitted to FBI Director William Sessions in late May.

FBI spokesman Milt Ahlerich said Sessions and his senior staff are reviewing the report and will promptly provide detailed information to congressional oversight committees. But he said it is premature to say whether the bureau will change any procedures.

Sessions told The Washington Times on Thursday that the review shows there was "sufficient and proper" reason for the bureau to probe CISPES.

The report, however, is highly critical of how the FBI handled informer Frank Varelli, whose information supplied much of the basis for the bureau's investigation of CISPES.

The internal report said there was a lack of proper supervision of Varelli and that he received certain information from FBI files that he should not have gotten, according to the sources.

The internal FBI review found no evidence that the bureau was involved in break-ins at offices of CISPES and other groups opposing U.S. policy in Central America.

The investigation of CISPES began March 30, 1983, prompted by tips that key members were involved in covertly furnishing funds and material to the FMLN, a leftist group seeking to seize power in El Salvador.

It was closed in June 1985 when the Justice Department concluded the group was involved in political activities protected by the First Amendment and not in international terrorism.

Varelli, a former evangelist from El Salvador, became a paid informer for the FBI's Dallas office in 1981, the same year the bureau began a probe of CISPES for possible violation of the Foreign Agents Registration Act.