A young man is being questioned by police in connection with the death of Ayrshire barman Stuart Walker.It is understood that an 18-year-old was taken into custody on Thursday evening.Mr Walker, 28, was beaten and burned in an attack in his home town of Cumnock, shortly after he was seen leaving a party.Mr Walker\'s body was found at about 05:00 on Saturday near the town\'s Caponacre Industrial Estate.