A former Transport for London (TfL) board member is facing fierce criticism after dismissing three suspected graffiti artists found dead on train tracks this week as “common scum”.

The bodies of the men, aged between 19 and 23, were discovered on Monday morning at Loughborough Junction train station, in southwest London.

In a now-deleted Twitter post, Brian Cooke wrote that dead men were not graffiti artists but rather “criminals who cost the railway millions and keep fares high”.

@BrianCookeBeck if this is really your words - this is part why they call the @Conservatives the #nastyparty pic.twitter.com/yFftl2SHPP — Morel Books (@MorelBooks) June 19, 2018

The TfL Code of Conduct says that members of its board - which is chaired by London Mayor Sadiq Khan and currently includes several doctors and CBE winners - are expected to “promote the highest standards of conduct”.

Cooke, who served on the TfL board for more than three years, was suspended from his role as chairman of Beckenham Conservative Association last month over another incident on the social media platform. Cooke was condemned for using obscene language against the Liberal Democrat former mayor of Bromley, Ian Payne, and for calling him a “shameful excuse for a Christian human being”.

The disgraced Tory was also sacked as chairman of the consumer watchdog London TravelWatch “after declaring his support for Boris Johnson days before the 2008 mayoral election, breaching the terms of his appointment”, says the London Evening Standard.

Responding to Cooke’s latest tweet, Sam Webber, the Lib Dem candidate for Bromley and Chislehurst at the last general election, said: “He certainly shouldn’t be saying things like this about a very sensitive and tragic incident. After being suspended by the Conservatives you would think he would know better than going on Twitter and ranting about this incident.”

Angela Wilkins, the Labour group leader on Bromley council, has called for Cooke to be expelled from the Conservative Party.

“They should take further action. It’s outrageous,” Wilkins said. “He should be thrown out of the party. The guy shouldn’t be involved in politics at any level.”

That view is shared by Marc Vallee, who spent a year documenting a London graffiti crew. Vallee told The Guardian: “His comments are callous and insensitive, especially at this very early stage, and especially from a former TfL board member.

“I would hope that if he is still a member of the Conservative Party that the transport secretary and others would say that he has brought his party into disrepute and expel him.”

A Tory party spokesperson said: “Brian Cooke has been suspended pending investigation.”