The Polish government today ordered two U.S. diplomats to leave the country after accusing them of receiving information "harmful to Poland" from a Polish scientist.

The expulsion order, the first such move since December's military takeover, came amid an intensifying campaign accusing the West of encouraging resistance to martial law. It appeared likely to result in a further worsening of already poor relations between Poland and the United States.

A television news commentator named the two American diplomats as John W. Zerolis, the science attache at the embassy, and James (Dan) Howard, the cultural affairs officer. A U.S. Embassy spokesman later said that the diplomats had been told to leave Poland by Friday.

Polish television said the decision to expel the two men was made after they were caught receiving documents from Ryszard Herczynski, a scientist with the Polish Academy of Sciences and former internee. The incident took place Sunday at Herczynski's apartment in Warsaw.

The U.S. Embassy's version of the incident was somewhat different. A spokesman, who asked not to be identified, said the diplomats had visited Herczynski with the intention of scheduling a meeting with a National Science Foundation official scheduled to visit Warsaw next week.

The spokesman said the two diplomats were accosted by police on their way out of the apartment and treated "very poorly" despite showing their diplomatic identification cards. He said they were made to stand spread-eagled against the wall as their pockets were searched and their personal belongings seized.

This evening U.S. Ambassador Frances Meehan was summoned to the Foreign Ministry and told about the expulsion orders by Deputy Foreign Minister Marian Dmochowski, who said the diplomats had been engaged in "activities prejudicial to the process of stabilization in Poland."

State Department spokeswoman Susan Pittman said in Washington that American diplomats were "manhandled" by men who "burst into apartment showing no identification whatsoever nor identifying themselves." A photographer later arrived and took about 50 photographs, she said.

"The actions of the Polish police, if that is who the intruders were, are unacceptable and clearly violate international law and diplomatic practice," she said.

Pittman said Meehan protested the Polish actions to Dmochowski. She identified the materials taken from the U.S. diplomats as "three standard Solidarity bulletins and two copies of proposals for scientific exchange grants."

The State Department refused to comment on further steps being considered.

Polish television tonight showed a picture of the document alleged to have been given to the diplomats, which it said described the reactions of Polish intellectuals to martial law. The commentator said that Herczynski, described as "a prominent Solidarity activist," had been arrested and was under investigation by the military prosecutor.

During the past week, the Polish press has stepped up criticism of Western countries for allegedly "interfering in Poland's affairs." Newspaper commentaries have accused American and Western European journalists here of giving "instructions" to Poles on how to resist martial law.

The most recent example of such an "instruction" was the information carried by Western radio stations and news agencies that the suspended Solidarity trade union is planning a 15-minute strike Thursday in protest against five months of martial law. Polish officials have claimed that the spreading of such information encourages antigovernment demonstrations such as those in Warsaw and other cities this month.