Darren Oxley, aged 38, fled the UK after his drug dealing operation in former city centre nightclub Republic was exposed in 2001.
Now he is being hunted by Thai detectives after Donald Whiting, 65, was gunned down outside his retirement home on an estate in a Thai resort managed by the ex-doorman.
Oxley, who fled Sheffield for Thailand and became a property developer and manager in the resort of Hua Hin, had been accused of sending extortionate water bills to Mr Whiting.
He was already due at court the day after the shooting, last October, over complaints lodged by Mr Whiting about his bills and having his water cut off. Mr Whiting also claimed his car had been firebombed.
But the day before the case was listed the pensioner was shot in the back of the neck, and has been left paralysed from the waist down.
Oxley is alleged to have been involved in a war of words with Mr Whiting on an internet forum, which is said to have left him furious at the damage done to the reputation of his company.
His Thai wife, 31-year-old Janpen Oxley, has been arrested for allegedly ordering the 'hit' on Mr Whiting. She was seized as she tried to cross the border into Cambodia. Thai police believe her husband may have already crossed the border and gone to ground.
Immigration Police Colonel Benjapol Lortsawat said: "An arrest warrant has been issued for Darren Oxley but his whereabouts are unknown."
Three others have been arrested for firing the gun at Mr Whiting in return for an alleged £4,000.
Oxley fled Sheffield after he was caught in 2001 paying drug pushers to deal cocaine, Ecstasy and amphetamines to revellers at the Matilda Street club in return for free entry and drinks.
South Yorkshire Police uncovered his lucrative sideline after mounting one of the largest raids ever carried out in Sheffield, which led to the seizure of 900 ecstasy tablets and 42 bags of white powder.
Oxley was charged with dealing Class A drugs but jumped bail, leaving nine members of his gang to face the court. They were jailed for a total of 60 years.
At Sheffield Crown Court it was claimed Oxley was the ringleader of the operation and his crew had "lived in fear" of him. He was described as "violent" and "not a man you mess with" who had made considerable amounts of money.
When he arrived in Thailand he bought flash cars including a Lamborghini, Bentley and Range Rover, went into the property trade, and married the ex-wife of a Thai police officer.





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