A former Tory activist who appeared to offer to "broker" the hiring of contract killers in an undercover film report previously worked for Conservative headquarters.
Jack Ross was contracted to do social media work for the party until earlier this year, the BBC has been told.
It comes after Conservative leader Kemi Badenoch referred to them as "shocking allegations", adding that she did not "believe that person is a member anymore".
A Conservative spokesman said Ross's party membership had "been suspended with immediate effect pending an investigation". It has reported that Ross said his words were not meant to be taken seriously.
Ross was paid to provide social media advice to the party for a brief period, the BBC has been told. He was never an employee or Conservative Campaign Headquarters pass holder.
However, he met Badenoch on several occasions as part of his role as chief executive of Turning Point UK, an offshoot of a right-wing American organisation.
Ross has also met several other right-wing politicians including the former Prime Minister Boris Johnson and Nigel Farage, the Reform UK leader.
In undercover filming broadcast this week by Al Jazeera, Ross appears to offer to "broker" the services of contract killers.
The Al Jazeera report said its undercover journalist approached Ross in 2022 with a fictitious situation of a family business at risk of being taken over by a criminal gang.
Ross is alleged to have asked the undercover reporter what was needed from him, and listed violent options that could be bought including stabbing, shooting and killing.
Al Jazeera said Ross denied the finding "completely" and claimed everything he said to the reporter was not meant seriously.
Turning Point UK has been approached for comment.