The Central Intelligence Agency may have been involved in "open air" biological warfare tests in streets and tunnels in the New York City area in 1955 and 1956, according to an analysis of CIA records released yesterday by the Church of Scientology.

The four-month analysis suggests that The CIA purchased supplies for experiments that included the dissemmation of unknown substances for aerosol devices mounted in suitcases and in the exhaust of a specially modified 1953 Mercury, according to the church's report.

The church's analysts said they examined about 600 pages of CIA financial records that were part of the agency's MK-ULTRA mind control experiments. The documents have been made public by the CIA during the last 2 1/2 years. t

The Scientologists' report is to be made public today. Copies of the report were sent to congressional Intelligence and Armed Services committees as well as to the Cia and the Army, a church spokesman said.

The Scientologists said analysts had pieced together scattered bits of information they found in the heavily censored CIA documents. They said they believe the biological warfare experiment was code-named "Operation Big City," and that details of the operation have either been destroyed by the CIA or are still shielded by a top-secret classification.

The CIA had never acknowledged any involvement with open air tests of biological agents. Much of the intelligence agency's biological testing during the 1950s was conducted for the agency by the Army.

Previously released documents and congressional hearings showed the Army's "Special Operations Division" at Fort Detrich, Md., carried out a series of tests between 1949 and 1968 apparently designed to gauge the vulnerability of American metropolitan areas to possible Soviet chemical and bacteriological warfare.

Early this year, a San Francisco lawyer released Army documents obtained under the Freedom of Information Act describing a 1950 test in which a bacteria cloud sprayed from a ship off the Golden Gate wafted inland to cover the entire bay area.

"We feel that the public has a right to know of every incident where U.S. citizens may have been the target of chemical and-or biological warfare testing," said Church of Scientology spokesman Brian Anderson.

From the 75 pages of receipts, church investigators concluded:

"Equipped with test animals, the CIA-Army team experimented with a variety of devices capable of disseminating a powder or gas into the air under covert conditions. Battery driven 'dusters' were installed in suitcases that had been soundproofed to muffle the noise. Similar devices were also constructed to sample the air to determine the effectiveness of the test. Personnel were protected with, at least, nasal filter pads.

"The primary test occurred Feb. 11- 15, 1956, in the New York City area when a 1953 Mercury with tail pipes extending an extra 18 inches traveled only 80 miles but covered four turnpikes and tunnels. When the test car returned it was washed to handle 'contamination' and washed again a few days later."

A church spokesman said, "We would like to know, and are sure the people of New York would like to know, what the ARMY-CIA used in 'Operation Big City.'"