THE MAN with the megaphone ran into the block of flats and up the steps, a few friends following closely. He moved along the outdoor corridor on the second floor until outside a particular door. Then he turned his back on it and addressed a crowd of about 1,000 below.

"That's the wrong door," someone shouted up. The megaphone man moved to the left, to the front of the next-door flat. "There's a man in these flats he began. "Get the fucker out!" shouted some of the crowd. Meanwhile, the occupant of the first flat emerged bewildered. A moment ago his flat was about to be branded the home of a drug dealer. Now, with relief, he realised the target was the man next door.

The anti-drug protesters who marched through Dublin's north inner city on Thursday night stopped at five or six flats and houses over the course of the hour-long march. They warned the occupants: "You have 24 hours to get out or we'll get you out."

At one house three young men looked down at them from an open window. The crowd shouted abuse. "Youse are fucking pushers in there!"

"We're from the country," called one of the youths, by way of a plea of innocence.

"What did he say?"

"He says they're from the country."

At some of the locations the leaders of the march shouted the name of the alleged dealer, or a whole family of dealers, as the crowd shouted anti-drug slogans. Once or twice the crowd seemed on the verge of rushing into a flat to evict the occupants, but it always held back.

Policing was low-key. Gardai watched as the alleged dealers' homes were identified. There was a time, not so long ago, when gardai told march organisers they must keep people moving, there could be no halting to protest outside individual houses or flats. Now the few gardai at the front of the march waited for it to move again, then cleared traffic from the route, asking the march organisers which way they were going.

The event had an undertone of violence but passed peacefully. There was a minor incident as it ended when a garda asked a young man driving a van behind the march for his name and address. The youth responded by blasting the van's horn until part of the crowd ran back and gathered around the garda and three colleagues to complain about "harassment".

The Labour TD, Mr Joe Costello, who was among the marchers, sought to calm matters and asked the garda whether it was really necessary to stop the van. The gardai stood their ground for a few minutes, while another marcher facing them shouted that they were "a bunch of shitbags". And then, wisely, the gardai walked away.

This time last year a similar march through the north inner city attracted about 300 people, and despite its serious purpose the marchers were amicable, waving at friends and neighbours. Last Thursday night's march was angry, with a large group of men who were not at last year's march leading the way.

THE meeting in a Buckingham Street bingo hall which preceded the march had also shown evidence of new stridency in the anti-drug movement. One young woman told the packed hall how the local anti-drug committee in her block of flats had approached her.

"The committee told me I had 24 hours to stop or get out, so I've stopped dealing," she said. The crowd applauded.

Others told a similar tale, apart from a man in his mid-30s who seemed more nervous than the rest.

"I got two anonymous phone calls telling me to stop dealing smack from my house," he said. "I'm not dealing smack, I'm working to feed my own habit and that's all, so lay off with your threats or be a man and say it to my face." Even he received respectful applause.

Fear is a weapon that the anti-drug movement in the north inner city is now using far more readily than it was a year ago. The fear is of vigilantism and violent eviction. The Inner Cities Organisations Network, which arranged the meeting and the march, is committed to drug protests by "peaceful means". But there is an obvious danger that the now weekly protest marches are building an atmosphere in which vigilantes will feel assured of popular support.

One of the leading protesters acknowledged there is now a much "harder edge" to the anti-drug movement. But violence is rare and usually blamed on "a few hotheads". Whether the "harder" element could be controlled, he said, would depend on how quickly the authorities responded to demands, such as the eviction of dealers by Dublin Corporation.

Despite the incident involving the gardai at the end of the march, and allegations of harassment of protesters, it was evident the gardai have approached the protests carefully since the minor riot on August 21st in Summerhill in central Dublin. Then the gardai were accused of over-reacting when men in riot gear were sent to break up a crowd. ICON says it is working to maintain a good relationship with the police.

There are links forming among anti-drug groups throughout the city, but as yet there is no cohesive policy. In Dolphin's Barn in the south inner city, where the drug addict Josie Dwyer was beaten to death by a vigilante gang last April, a much harder anti-police line has been emerging than north of the Liffey. There is a suspicion that some activists there with links to the IRA expect to be arrested shortly over the Dwyer killing and are trying to whip up anti-Garda feeling in advance.

In Tallaght - where two alleged dealers faced a protesting crowd outside their home earlier this week - Sinn Fein activists are more overtly involved in the anti-drug movement than elsewhere. They say they are acting as community leaders and are not promoting a republican agenda. But there is a strong prospect of anti-drug candidates supported by Sinn Fein emerging at the next Dail election.

Whatever these alliances and aims, it remains the case that eviction and anti-police messages are easier to "sell" to a frustrated crowd than reports of meetings with Departmental officials. And, while Garda and protest activity are disrupting the drug trade in some areas, very often it only shifts to neighbouring streets. When activity stops, the dealers return.

THERE is a sense of growing pressure which echoes the mid-1980s. Then the Concerned Parents movement was divided over co-operation with the Garda and a series of violent incidents led to the arrests of some anti-drug activists.

Many involved in the Concerned Parents then are back on the streets now. There have been changes over the intervening decade. More facilities are available for addicts. The Garda has greater powers, many provided by this Government in anti-drug "packages".

But the drug problem has grown, with the estimated 7,000 heroin addicts in Dublin now joined by thousands of ecstasy users. And, despite successful prosecutions of dealers and longer sentences, residents in the most drug-infested areas feel the gardai and the criminal justice system cannot cope.

Against this background those dedicated to "peaceful" protests are still managing to restrain the more militant. But for how long?