WARSAW, DEC. 10 -- Emigre businessman Stanislaw Tyminski, who was soundly defeated by Lech Walesa on Sunday in Poland's first direct presidential election, was barred today from leaving the country pending investigation of allegations that he criminally slandered government officials during his campaign.

Tyminski, who holds Polish, Canadian and Peruvian citizenship, has been ordered by prosecutors to report for "interrogation and clarification" on Dec. 17 in connection with his campaign attacks against then-Prime Minister Tadeusz Mazowiecki before the first round of the presidential election Nov. 25.

Tyminski, who had emigrated to Canada 21 years ago and was virtually unknown here until he returned to campaign for the presidency, could not be reached for comment.

The Polish press agency reported tonight that he and his wife had reserved airplane tickets for a Dec. 12 flight to Canada via London.

He received the summons two days before the election, the agency said.

Election officials, meanwhile, released unofficial results showing that Walesa received 74 percent of the vote Sunday and Tyminski 25 percent, with Walesa getting 10.6 million votes and Tyminski 3.6 million. In the six-candidate first round, Walesa had received 40 percent, Tyminski 23 and Mazowiecki 18.

Sunday's results showed that while Walesa had won in each of Poland's 49 administrative districts, Tyminski polled as high as 40 percent in at least five districts in the center of the country. Those areas contain the small towns where Tyminski's frequently demagogic promises of quick riches drew support.

The results led several of Walesa's oldest Solidarity advisers to temper their congratulations today with a note of warning.

While Walesa, as president-elect, paid a sentimental visit today to the Gdansk shipyard, where he launched his career as a labor organizer and anti-Communist politician, prosecutors here said they had evidence that Tyminski's attacks on Mazowiecki amounted to a criminal offense under a law that forbids acts that "demean the top state authorities."

The offense carries a jail term of six months to eight years. Prosecutors said Tyminski would be stopped by border police if he attempted to leave the country.

The alleged slander took place during a campaign rally in Zakopane, where Tyminski, waving documents, claimed to have incriminating evidence that the Mazowiecki government was selling state-owned factories to foreigners for less than their value. The documents, however, turned out to be a list of several factories' monthly incomes.

Tyminski also had claimed, during a televised press conference, to have incriminating evidence against Walesa "of a serious personal nature." He refused Walesa's demand to show the supposed evidence on television.

Walesa accused Tyminski of attempted blackmail and charged that he was a front man for former Communists trying to mount a counter-revolution in Poland.

Newspaper editor Adam Michnik, a prominent Solidarity theoretician who was one of Walesa's bitterest critics, said today that the election results revealed "a new picture of Poland -- a society filled with intellectual chaos, xenophobia and aggressive populism, and a yearning for the power of a strong hand. The new president has a great duty to remove these pathologies."

Former Solidarity parliamentary leader Bronislaw Geremek said he believed Walesa's greatest challenge would be to convince Polish society that painful reforms begun by the Mazowiecki government need to be continued.

In his visit to the Gdansk shipyard, Walesa, a former electrician there, greeted old coworkers and pledged not to forget his roots.

"I know where this white shirt of mine comes from," he said. "My clothes were once the same as yours, and sometimes even worse. The most difficult thing was to change those clothes.

"But thanks to that, I will always remember you and I will return here."