NILES, Ill. (AP) _ Anti-abortion demonstrators disrupted a speech Tuesday by Democrat Michael Dukakis to Polish-American supporters, some of whom physically ejected a few of the protesters in a melee of pushing and shoving.

Some punches were thrown, but police said there were no arrests in the incident, the most serious in a series of anti-abortion protests at appearances by the Democratic presidential nominee in recent weeks.

Dukakis, after the interruption at the start of his speech at a banquet hall in this Chicago suburb, delivered his prepared remarks in which he emphasized economic themes and said his Republican rivals ''love to blame American workers first.''

He ridiculed Republican presidential nominee George Bush for saying last fall that Detroit automakers could use the abilities of Soviet tank mechanics.

''He said the American auto industry could use a few good mechanics from the Soviet Union who could teach our workers something about quality,'' Dukakis said. ''Do you really believe we in America have anything to learn from a society where workers have no rights, consumers have no choices, and even Mr. Gorbachev admits their economy is a shambles?''

''Those Republicans in Washington love to blame American workers first,'' he said.

Last fall, during a trip to Europe, Bush said he'd been told in a meeting of NATO ministers that 350 Soviet tanks had completed maneuvers without a breakdown.

''Hey, when the mechanics who keep those tanks running run out of work in the Soviet Union, send them to Detroit because we could use that kind of ability,'' Bush said at the time. Later, he apologized to U.S. autoworkers, adding, ''Hey give me a break; I didn't mean anything by it.''

Following his appearance, Dukakis told reporters that protests such as the one he faced were to be expected.

''It's a democracy and those of us in public life know from time to time that there are going to be people who may tend to be a little loud and disruptive,'' he said.

''I just hope as the campaign goes on we can address the real issues that face the campaign and that face the country and do so in a way that's respectful of each other.''

Dukakis repeated his position that he opposes abortion but that ''in the last analysis it's up to the woman in the exercise of her own conscience and religious beliefs to make that decision.''

Dukakis ran into trouble of a different sort when he tried to leave Illinois for a campaign event in Columbus, Ohio. Federal Aviation Administration officials pulled a surprise safety inspection of his chartered Presidential Airways Boeing 737, grounding him in Chicago.

He canceled the Columbus appearance and flew back to Boston on his backup plane, accompanied by as many news people as the plane could hold.

After landing in Boston, Dukakis told reporters that the timing of the FAA's spot inspection was ''very curious,'' but declined to comment further.

Campaign spokesman Dayton Duncan said the inspection could have been performed overnight, ''not 15 minutes before we were supposed to leave.'' Later, he added, ''We're looking forward to the moment in January when he gets to name the FAA administrator.''

Stan Rivers, acting administrator for the FAA regional office in Chicago, said, ''It's not a new policy. It goes on in every campaign.''

During the speech disruption earlier, Dukakis told the protesters, ''I respect your right to disagree with me. That's what a democracy is all about. ... I would hope you would respect my right to speak.''

When the demonstrators refused to quiet down, a half dozen or so were forced out of the crowd of some 1,000 people. In the back of the room protesters and others in the crowd scuffled. Several punches were thrown at the protesters.

The people who evicted the protesters did not appear to be security personnel, and campaign spokeman Dayton Duncan said they were not campaign workers. Secret Service agents protecting Dukakis did not move toward the protests.

Just as Dukakis was about to begin, the protesters had shouted ''What about abortion?'' The crowd tried to drown them out by chanting ''We want Mike.'' As Dukakis tried to proceed, other protesters shouted ''You're a baby killer.''

One protester, Richard Freeman, 46, of Chicago, said members of several area anti-abortion groups met a week ago to plan protests of any Dukakis events. ''If Dukakis is within 300 miles of a pro-life activist, they're going to go out and greet him,'' he said.

Joseph M. Scheidler, executive director of the Pro-Life Action League, said the group obtained tickets to the event from the Democrats, ''and we decided we were going to inject the issue of abortion whenever it seemed relevant.''

One spectator obviously upset by the demonstators, Marion Reis, said he opposes abortion and has donated money to pro-life groups. He said he would make no further donations, adding, ''I think they're full of hate, not full of love.''

There seemed to be only a handful of protesters inside the hall and perhaps 20 or 30 outside.

One day earlier, more than 100 demonstrators chanted as Dukakis met outdoors with residents of a South Philadelphia neighborhood. Other groups of similar protesters have shown up to heckle him but previously had not delayed him from speaking.

On Tuesday, Dukakis also met in private with Illinois Democratic leaders, not including Jesse Jackson who was said to be upset about that omission.

Dukakis' state press secretary, Judy Erwin, said Jackson was not included in the meetings because he is regarded as a national leader and Tuesday's meetings were to focus on the Illinois state campaign.

In Niles, Dukakis paid tribute to the Polish trade movement Solidarity and its leader, Lech Walesa, saying the Polish government ''must engage in a productive dialogue'' with the union. ''Solidarity must be recognized,'' Dukakis said.

Dukakis repeated his economic themes that contend the American middle class has been caught in an economic squeeze, with declining buying power and stagnant wages, during the Reagan administration.