Police have now taken action to remove the Facebook profile of Shaun Pepperell, of Burnthouse Lane, Wonford, after scores of threats were posted on his page against one of his former drug runners Wayne Martin.
Pepperell, 37, a youth football coach turned drugs ringleader, was sent to prison for 13 and a half years after pleading guilty to two counts of conspiracy to supply cocaine and one of conspiracy to supply cannabis.
Martin, from Exeter, whose willingness to give evidence led members of the drugs gang to abandon a planned trial and change their pleas to guilty, is yet to be sentenced for his role.
His whereabouts are unknown after he became the first person in Devon and Cornwall to be put in the witness protection programme.
A Facebook friend of Pepperell, who has read almost 100 threats posted from people around the country under a big picture of Wayne Martin, said he should fear for his life.
The friend, who asked not to be named, said: "The threats include 'I am going to kill you', 'you are dead', and 'you deserve to die you grass'. These were from named individuals on the web, and some of them are very nasty characters.
"I would have thought that if the police had seen this they would surely take action against these people. If I was Wayne Martin I would fear for my life. He is supposed to be in police protection, but his face was plastered all over Facebook. These are vengeful people who feel very bitter towards him.
"Wayne has made his bed and has to lie in it, but you cannot have people's lives threatened in such a public way and the police not take action."
Detective Sergeant Wes Snell, who led the investigation into the gang, said officers were aware of the situation but considered it closed after contacting the social networking site asking it to remove the page.
He said: "We are aware that some inappropriate comments were posted on Facebook which our officers saw and they decided the most appropriate action was to get the Facebook page removed. We contacted Facebook and they took it down straight away and we now consider that matter closed.
"If something more serious comes out of it we will investigate. But we think with time things will settle down and that the comments were an instant reaction to the sentence when emotions were running high.
"I would imagine it is because he is in witness protection that these comments were made. They know he is safe, so this is a way of them venting their frustration and anger."
Pepperell was said to be the ringleader of the gang, arranging drug runs that brought hundreds of thousands of pounds of cocaine and cannabis into the city.
The Echo revealed recently that he was a successful under 11s football coach, and that the children were said to be devastated by his conviction.
The other defendants were said to be the couriers who travelled across the country to pick up the drugs and hand over the money.
Jason Hutchings, 38, from Whipton, was sentenced to eight and a half years in prison for conspiracy to supply cocaine and cannabis, while Neil Western, 36, and also from Whipton, was given five years and nine months for conspiracy to supply cannabis.
Also jailed were Matthew Mingo, 20, of Coleford, Crediton; Gavin Squires, 32, of Tedburn St Mary; Patrick Hurley, 61, from Tedburn St Mary, and Christopher Land, 27, from St Thomas.
Joshua Sprague, 20, from St Thomas, was given a nine- month prison sentence suspended for two years.