GARDAI are investigating an organised crime ring among foreign-organised phone thieves who enter the country on false passports, steal millions of euro worth of mobile phones and ship them out of Ireland, mainly to Africa and eastern Europe.

Sources in the Muslim community here say there is rising concern among the law-abiding community about the large numbers of young criminals coming here. The sources say the thieves are travelling on false documents, entering the country on flights from Spain, Greece and Portugal.

Garda sources in Dublin are aware of the identity of two Algerians, understood to be brothers, who were believed to have been involved in a recent stabbing incident in the city centre. The incident is believed to be connected to the organised phone thefts. But they have since disappeared and may have left the country. One is wanted in England on theft charges.

Gardai say large numbers of foreign thieves are being attracted here as word has spread about the State's lenient treatment of offenders and the near certainty of bail after arrest. And they say millions of euro worth of phones are being shipped out of the country by the gangs from north Africa, Nigeria and eastern Europe.

Last November gardai recovered a substantial amount of stolen phones and when they checked the personal phone of one of the thieves he had sent a text to an associate in Nigeria telling him to come to Ireland as "it is a virgin country . . . there is plenty of money to be made".

Gardai say the thieves work mainly at night, mixing with drinkers in the city centre, stealing phones, wallets and purses.

Mobile phone theft is the fasting rising category of crime in the country. Although exact figures are unavailable, as many victims simply think they have lost their phones, the figure could be between 20,000 and 40,000 annually.

More than 1,000 phones valued at €430,000 were reported stolen in January and February in Dublin city centre alone.

Gardai said 60 per cent were reported stolen in bars, cafes and nightclubs and reported stolen in the two main city centre stations, Pearse Street and Store Street.

The organised gangs responsible for the theft and sale of the phones are mostly from outside the country.

Gardai say that many of those arrested have previously been arrested in other EU countries.

Chief Supt Michael O'Sullivan of Pearse Street urged people to keep a note of their IMEI number, the identifying number which allows phone operators to disable the phone even if a new Sim card is used. However, the phone can be reactivated if the phone is moved out of the country. Gardai say this is what is attracting the large numbers of foreign thieves here.

The two Algerians being sought by gardai are understood to have frequented a cafe in south inner Dublin which gardai believe to be a hub for selling stolen phones. It is understood gardai arrested a north-African man near the cafe earlier this year with a shoulder bag containing 40 stolen phones.

Sunday Independent