Chelsea manager Avram Grant has been subjected to racist death threats after a package arrived at the club's Cobham training ground containing a suspicious white powder.

Grant is now under the guard of Special Branch police officers after returning from Greece, where he was overseeing the Blues' 0-0 Champions League draw with Olympiacos.

A member of staff opened the envelope, which contained a note which read: "You are a back-stabbing Jewish b*****d. When you open this letter you will die a very slow and painful death."

Threats were also made against the manager's wife, while the author claimed the powder was lethal. Tests subsequently revealed that it was harmless.

Surrey police stated: 'We are investigating a suspicious package which was received at the Chelsea training complex.

"A white powder found in the package was analysed by specialists and has been determined to be harmless."

The complex was quarantined by the emergency services while tests were carried out and staff tested.

Grant's appointment from his previous role as director of football at Chelsea was unpopular with fans as it saw the exit of Portuguese Jose Mourinho, who had won two titles alongside cup triumphs at Stamford Bridge.

Jonathan Symcox / Eurosport