Illicit drug problems are growing in Northern Ireland, and as three men are set to appear today at Belfast Magistrates Court on drugs charges, it has emerged that even inmates in the Province's prisons are heavily involved, with almost 600 of them having failed drug tests.

Today's court appearance follows the seizure of suspected cannabis resin - with an estimated street value of £350,000 - in the Short Strand area of Belfast at the weekend.

A 25-year-old man has been charged with possession and possession with intent to supply.

Another 25-year-old man and a 32-year-old man have been charged with being concerned in the supply of cannabis resin.

In addition, another man, aged 31, was held last night in connection with the incident in the Short Strand.

However, even if convicted and given custodial sentences, drugs remain as part of the scene behind bars too.

Prisoners failed almost 600 drug tests in Northern Ireland jails last year – with a further 400 inmates refusing to undertake the voluntary testing.

They were discovered to have taken a range of illegal substances, including cocaine, cannabis, amphetamine, opiates, non-prescribed tranquillisers and sedatives such as diazepam.

In addition, there were almost 1,800 drug finds made across Northern Ireland's three prisons in the past five years, including 400 last year.

The figures, released under Freedom of Information legislation, have led to calls for tougher measures to be brought in to tackle the problem.

NI Policing Board Member Peter Weir said security at Northern Ireland jails – which currently house approximately 1,000 sentenced prisoners and another 470 on remand – had to be reviewed.

"The amount of drugs getting into prisons is deeply disturbing," he said.

The North Down DUP MLA added: "I think most people would find the figures fairly shocking."

Some 580 drugs tests were failed across the Province's three prisons - Maghaberry, Magilligan and Hydebank Wood - during 2007. That amounts to 12% of the total 5,007 tests conducted for drugs.

A Northern Ireland Prison Service spokesman said: "We take very seriously the problem of drug abuse and use a system of voluntary drug testing as part of the progressive regimes which operate in all establishments."

Drug testing within the prison system in Northern Ireland is voluntary for the prisoners, with more than 400 refusals last year.

The spokesman said mandatory drug testing is being considered by the Government and is already in place in England and Wales.

He said the Prison Service used a number of methods to detect drugs including physical searches, conducted on a regular but random basis, of inmates, staff, visitors and cells.

Drug detection dogs were used in a bid to halt illegal substances entering the jail.

(BMcC)