The father of a man who took his life after allegedly being bullied in the Conservative Party has laid the blame on the party chairman.
Ray Johnson, whose son Elliott Johnson was found dead on railway tracks in September, said responsibility for the tragedy rests on Lord Feldman's shoulders.
The party has said an investigation into claims of bullying in the youth wing will be conducted "in its entirety" by the law firm Clifford Chance.
Former party co-chairman Grant Shapps announced at the weekend he was standing down as an international development minister following claims he failed to act on reports of bullying in Conservative Future.
But pressure continues to mount on Lord Feldman - an old university friend of David Cameron who was co-chairman with Mr Shapps until the general election in May.
Mr Johnson told BBC Radio 4's Today programme: "Lord Feldman was in charge when my son was being bullied and when my son died. Shapps had left CCHQ several months earlier so the responsibility lays squarely on the shoulders of Lord Feldman."
The allegations centre on the activities of the former activist Mark Clarke, who was expelled from the party earlier this month. Mr Clarke has strongly denied the allegations against him.
Mr Johnson said Baroness Pidding, who worked closely with Mr Clarke on the Road Trip election campaign, said it had been a "mistake" to introduce her to the House of Lords shortly after his son's death.
He added: "She is obviously a person who needs to be questioned about her role."