IT was dusk when the van arrived at the edge of Brickfield Park in Harold's Cross. It flashed its headlights. At the signal a group of about 20 young men began to walk towards the van as one of its occupants got out.

Gerard Kavanagh (25) had £1,300 in his pocket - a sum many would consider quite a lot for an unemployed man to be carrying. But he also had packets of drugs stuffed into pockets and down his trousers. As he went towards his gang of pushers he didn't think to look behind. Neither did his friend Liam Boland, who had stayed in the van.

A patrol car carrying three uniformed gardai had pulled up behind. The gardai knew whom they were after. There had been numerous calls from residents in the area about drug dealing at the park in the evenings, and the patrol car had shown up at just the right moment.

Garda Eamonn Maloney grabbed Boland (33) immediately as he sat in the van. Kavanagh turned to see what was happening, then took off at speed, dropping packets of drugs as he went. He was caught by the other two gardai, Martin O'Connell and Gary Corrigan.

Kavanagh was in real trouble. He told the gardai he had gone into the park because he had spotted someone there who had once broken the window of his car. But the packets of cannabis being picked out of the bushes told a different story.

At this stage Boland was "looking good". He wasn't carrying any drugs, he said Kavanagh had mentioned he was going to meet someone in the park and he had merely accompanied him.

But a search of Boland's pockets revealed two very incriminating pieces of paper. One was an application to the Eastern Health Board for rent to be paid on an apartment in Harold's Cross. The other was a Cablelink form with the same address. Boland realised with dismay what was about to happen.

WHEN the apartment was searched heroin with a street value of £100,000 was found inside. It was not well hidden - some was in a container under the sink, the rest in a glass jar in the hot press. There were electronic - weighing scales, plastic packets and all the paraphernalia of drug wholesaling.

That was in March 1994. In the two years since, both men have been out on the streets. They have been seen hanging around areas where drugs are dealt and have shown all the signs of enjoying the fruits of their business. Both made bail and received legal aid. Kavanagh got married, flew his friends to Manchester for his stag night, then had a wedding reception in Kildare which cost £7,000. Boland was less lavish, although he did drive a new car and spent free time at Blessington Lake on his £4,000 jet ski.

With the drugs found on Kavanagh and in Boland's home, it was clear the gardai had a very good case. But it was only in the last few weeks that the legal system ground its way towards dealing with them. Kavanagh got four years. Boland - who indicated he had bought the heroin - was jailed on Thursday for 7 1/2 years.

Their two years of liberty between being caught and sent to jail are part of the State's way of dealing with such criminals. Against this background, more people are turning to faster solutions, just as they did in the 1980s, so residents of Fatima Mansions, in the south inner city, have been clearing known drug dealers from their flats for about two months. A similar process has been under way in west Tallaght. But the activities of these groups have been peaceful: drugs dealers have been told it is time to leave, and residents have stood between them and their customers, noting car numbers and daring pushers to do their business in the open.

In west Tallaght these methods have been successful. In Fatima Mansions the number of dealers diminished but around Dolphin's Barn it seemed to grow, and some residents say the growth has been helped by Tallaght dealers moving back into the south inner city.

Joseph Dwyer (41) was one of the many drug addicts often seen around the junction at Dolphin's Barn. The AIDS sufferer was at most a small scale drugs peddler, selling to feed his heroin habit. His brother said at the time he died Mr Dwyer had only 87p in his pocket.

On Tuesday night at 9.30 p.m. Mr Dwyer ran into a gang of men who had come to the junction to "clear the Barn". The men - about 15 of them armed with sticks and iron bars - were well known to people who saw what happened.

Mr Dwyer - weakened by AIDS and weighing only 6 stone - had no chance against the gang, which cornered him in Basin Lane for a beating which lasted several minutes. A crowd of people watched some had run down from the junction to help "Josie" but were held back by members of the gang, who had blocked the lane.

Afterwards, Mr Dwyer was taken to hospital, arriving at St James's casualty unit just after 10 p.m. He was pronounced dead an hour later.

COMMUNITY leaders in Fatima Mansions are anxious to condemn the killing and there is a fear that all anti drugs groups will become tarnished with the vigilante tag. Against this background rumours are circulating that the vigilantes are not all they seem, and that there may have been more to Tuesday's killing than mob frenzy.

One dealer in Dolphin's Barn is said to have paid £60,000 to a gang including some of the vigilantes, to ensure his own safety. Another man from the area who was shot in a city centre pub earlier this year had received a letter shortly beforehand explaining that a few thousand pounds would buy him the "health insurance" he needed.

There are indications that group with republican links has been working to subvert the peaceful anti drug initiatives of residents in inner city communities. A threatening note received by one suspected dealer purported to be from the IRA.

There is no doubt that all of the suspected drug dealers in Dolphin's Barn, Mr Dwyer was one of the most vulnerable. Was he killed for being a dealer, or did he die because his killers wanted to make a point?

Whatever their motives, it is clear the vigilantes' activities up to the moment of Mr Dwyer's death can only have had some measure of popular support because of the slow pace of the State's response to the drug problem.

While condemning the murder, Democratic Left TD Mr Eric Byrne pointed out that it was taking six months for the State's forensic science laboratory to prove that substances seized from dealers were illegal drugs. In that time the dealers were back on the streets.

Reflecting on the two years it took to jail Boland and Kavanagh, one Dolphin's Barn resident said: "It makes people more ready to listen to the men who say they can offer instant solutions."