Police are investigating after the daughter of Dragons' Den star Duncan Bannatyne was allegedly threatened on Twitter.
A spokesman for Durham Police confirmed the businessman had reported receiving a number of threatening messages via the social networking site.
Police were investigating "the credibility of these threats", he said.
Posting on Twitter, Mr Bannatyne, 62, offered a £30,000 reward for any information leading to an arrest.
A police spokesman said: "Durham Constabulary can confirm Duncan Bannatyne has reported a number of threatening messages he had received via email and Twitter in which threats were made against a member of his family.
"These appeared to originate from an email address based in Russia.
"We have been liaising since then with Mr Bannatyne and conducting inquiries into the credibility of these threats."
A tweet from the account of a Twitter user named Yuri Vasilyev was posted to Mr Bannatyne on 31 July, saying: "I'm looking for a £35,000 investment to stop us hurting your Hollie Bannatyne."
Mr Bannatyne is reported to have responded: "I offer £25,000 reward for the capture of the coward who calls himself @YuriVasilyev_ Double if his arms are broken first."
These tweets were later said to be deleted, with Mr Bannatyne changing his Twitter offer to "£30,000 reward for info leading to his arrest".
Mr Bannatyne said in a statement: "My family is well protected but I take any threat to them very seriously and will do all I can to ensure the person or people involved are caught."