A DRUNKEN joker, whose hoax phone call sparked a major security alert, paid for his prank with his liberty when a judge at Salisbury Crown Court failed to see the funny side.

Christopher Prosser (22), called Debenhams in Blue Boar Row and, putting on a fake Arab accent, warned that the store would be the target of a terrorist attack.

Several businesses were evacuated and the street was cordoned off for two hours while police searched the area with sniffer dogs.

The cost of the operation and the loss of trade to the affected businesses ran to thousands of pounds.

Prosecuting, Colin Meeke said that Prosser had spent an evening entertaining his drinking mates by making a series of relatively harmless prank calls, for example, notifying people that they had won a free holiday.

But the joke wore thin when Prosser picked up his friend's mobile phone and used it to call Debenhams and pose as a terrorist.

Mr Meeke said: "Earlier on, his antics were a source of great merriment but he went too far. His friends told him immediately what a fool he had been but no steps were taken to do anything about it."

Nine hours later, when staff coming into work at Debenhams picked up the threatening message on the store's answering machine, a full-scale security operation swung into action.

The court heard that the mobile on which Prosser made the hoax threat was traced and he was arrested the same day at his home in Downton Road, Salisbury. He later pleaded guilty before Salisbury magistrates.

Defending, Michael Shaw described Prosser as "an immature young man who simply didn't think through the consequences of a stupid and foolhardy act".

He added: "His misplaced humour caused considerable disruption to the city and commerce of Salisbury and considerable angst to his parents."

Sentencing Prosser to 12 months in jail, Recorder Harry Martineau said: "Under the influence of alcohol you were all too easily tempted to behave selfishly, irresponsibly and dangerously.

"You had nine hours to put it right but instead you allowed many people to experience serious distress and fear that they might be the victims of a terrorist attack."