A health watchdog has confirmed a drug user originally from Glasgow has died after injecting himself with heroin containing traces of anthrax.

Four men were arrested after Thomas Forbes, from Loughborough, Leicestershire, died in hospital last Thursday after being poisoned. The Health Protection Agency said there was little risk to the wider population.

But Tim Davies, deputy director of public health for NHS Leicestershire County and Rutland, said heroin users in the area needed to be "extremely alert". The Health Protection Agency said Mr Forbes' death was the fourth case in England where anthrax had been found in an injecting drug user.

Since December 2009, there have been 47 cases in Scotland and one in Germany. It is believed the heroin, or chemicals cut with the drug, have been contaminated with anthrax.

Originally from Glasgow, Mr Forbes was the father to seven-month-old Dylan and was expecting a second child with his former partner Kelly in November. In a statement, his parents Fred and Christine and brother John said: "Thomas had lots of friends of which he always had time to enjoy their company and they all enjoyed his company and had plenty of time for him.

"He was full of character and continued to enjoy life with his family and friends to the end. Thomas was loved by all his family and friends and will be sadly missed."

Leicestershire Police said four Loughborough men, aged 24, 31, 35 and 37, have been arrested, questioned and bailed.

Detective Chief Inspector Mark Harrison said: "I would urge anyone who knows anything about Tom's death to contact us immediately. Any calls received will be treated in confidence."