A Dublin city school may close because of gangland activity, a meeting of former TDs and Senators has been told.

Dublin City Council assistant manager Brendan Kenny said that in a certain city complex, teachers are "very afraid that the school is going to be closed because there is a serious feud going on between a number of families".

He said that in the school, which he did not name, “gardaí are often called to protect kids in the playground”.

Addressing the Irish Association of Former Parliamentarians in the Seanad chamber, Mr Kenny warned the progress that had been made in dealing with crime and anti-social behaviour in disadvantaged areas could unravel.

“I would be very worried that with the cuts and reduction in services, things may go back so we need to keep concentration on it.”

There were fewer resources and Dublin City Council had 1,361 fewer staff than it had in December 2008.

“The risk is that we pull back from managing our housing estates and the problems will start again. Strong estate management is vital,” Mr Kenny said.

He called for a Garda unit to be specifically assigned to the local authority. “There should be just one management of estates, one management of streets. The unit would include gardaí, local authority staff, perhaps someone from the HSE and the social work side of things. Currently they do not co-ordinate effectively.”

He said there was more anti-social behaviour and more aggressive begging on the streets of Dublin. “There are only about 50 or 60 people on the streets causing difficulty but it is growing.” Many were young people with drug and alcohol addiction, who suffered domestic abuse and mental health problems.

Mr Kenny added: “Those problems do spawn criminality and problems quite often are allowed to fester for years and years and kids who are involved in anti-social behaviour become the gangsters and big criminals.”

Former Garda Ombudsman commissioner Conor Brady said there should be awareness of the "hidden costs of the Troubles which we continue to pay in the drugs problem".

Mr Brady, a former editor of The Irish Times, said: "Drugs and the IRA arrived together in the late 1960s as far as the Garda Síochána was concerned, but the responses to the two challenges were very different" and security of the State took priority.

By the time resources were put into dealing with illegal drugs in the 1980s, it was a “classic case of too little, too late”.

He said that in 1971, the drug squad had nine staff while in the same year, 600 extra gardaí were deployed to the Border.

Former detective superintendent Noel Clarke said organised crime had been near the top of the political agenda since the deaths in 1996 of Det Garda Jerry McCabe and crime correspondent Veronica Guerin.

He said there was a need to focus on informal ties between members of an organised crime group and they should be considered perhaps as “criminal co-operatives” rather than organisations with fixed leaders and structures.

Former president of the Law Society James MacGuill called for a mature debate on the legalisation of certain drugs. Figures show 26 per cent of people here used cannabis and they were “all in the hands of criminals”, because only criminals can supply these drugs.

A “licensed supplier would not have an agenda of creating an addiction to other more addictive substances”.

He added that “you would remove the foot soldiers of crime and you remove drugs on credit. Drug debt is a major start to people becoming involved in drug crime because that’s the only way they can clear the debt.”