DETECTIVES believe that drug dealers with loose associations with Dublin gangs are carrying out 'copycat' arson attacks on headshops around the country rather than the one criminal gang orchestrating the spate of incidents.

In the past month there have been four arson attacks on head shops, which sell a range of legal highs.

The Nirvana store on Dublin's Capel Street and two businesses beside it were destroyed after flames ripped through the premises on 12 February.

Five days later the Happy Hippy Store, on Dublin's North Frederick Street, was raided by an armed gunman who forced an employee and two customers into the backroom of the shop before he and an accomplice set the place alight. This attack has now been upgraded to a triple attempted murder investigation. The captives were forced to run through flames to escape but the fire did not take hold.

Last Wednesday, two viable explosive devices were discovered outside headshops in Athlone and were made safe by an army bomb disposal squad.

The next day, Yutopia, a head shop and adult entertainment store on Connolly Street in Sligo, was targeted when a crudely-made petrol bomb was thrown through the shop window, causing extensive smoke and fire damage to the interior of the shop. Two men were arrested in relation to this attack but have since been released without charge. A file is being prepared for the DPP.

There is major concern that other head shops around the country will now be targeted.

The National Bureau of Criminal Investigation (NBCI) has not yet launched a probe into the spate of attacks but may do so if more premises are targeted.