Despite assurances a year ago when Chile played host to the Organization of American States, the Human Rights Commission of the OAS has found that the military government there continues to violate most major rights.

Fewer persons have been arrested arbitrarily than in past years, but the government is disclaiming any knowledge of the whereabouts of a large percentage of them, the commission had found, leading it to surmise that the junts may have established secret detention centers.

The commission's special report on Chile is the third since the military seized power there in 1973. Each previous report has been sharply contested by Chile, with rebuttals of findings that indicated widespread torture, killings and imprisonment without judicial process.

The commission reports, however, that when it sought updated information from Chilean authorities, in part to test their contention that rights are being observed, it received "incomplete answers."

The latest report is to be presented to the OAS General Assembly's meeting next month on Grenada, in the Caribbean.

The commission reported that:

Measures ostemably designed to protect individual rights, including crestion of a civilian advisory council, have failed to end the deprivation of rights in Chile.

"Although the number of complaints of homicide brought Chilean authorities has decreased," the government has not satisfactorily explained the deaths that did occur. Chile acknowledged some of the homicides and contended that they were justified. The commission disagreed.

Of 109 persons reported to the commission to have been detained in 1976, 20 per cent "disappeared - that is, the Chilean government denies any knowledge of their location." In past years, the proportion of detained persons who "disappeared" was about 12 per cent.

"Also of grave concern is the expulsion of Chilean citizens, since personal liberty includes the right to remain in one's country."