A source said: "Blake is living in fear for Amy's and his own life. At first he thought the guys in jail with him were just trying their luck, but the threats have gotten more and more serious.
"They have ordered Blake to pay the £100,000 into a secret bank account within the next few days or else Amy will be snatched and harmed.
"Blake knows it would be easy for someone to bundle Amy into a car, he is worried sick."
Blake is being held on remand after allegedly conspiring to pervert the course of justice by bribing James King, the landlord of Macbeth's public house in Hoxton, to withdraw his allegation of grievous bodily harm (GBH) against the 25-year-old.
He will remain in custody until January 18 for a plea and directions hearing.