An aide to Labour's London mayoral candidate Sadiq Khan has been suspended over a series of offensive messages posted on social media.
Shueb Salar, a parliamentary assistant to the former minister, posted a string of messages on Twitter containing abusive language about women and homosexuals.
A spokeswoman for the mayoral hopeful said they were "serious issues" and Mr Salar had been suspended from Mr Khan's parliamentary office pending an investigation.
In one message, posted in May 2012, Mr Salar said "currently hating on all you faggots who have finished uni" adding "lucky c****".
A post from June 2012 read "f*** all you hoes" while a message from April 2012 suggested that the way to "treat a lady" was to "buy her a nice iron and extend the kitchen for her".
Mr Salar started working for Mr Khan in his Westminster office in November 2014, after the offensive messages had been put on social media.
But Cabinet minister Chris Grayling questioned Mr Khan's judgment in employing someone who had published the comments.
The Commons Leader said: "'These comments have absolutely no place in modern society.
"They raise serious questions about the judgement of Sadiq Khan who chose to employ this man despite his views being public, on a Twitter account followed by Khan himself.
"The mayor of London makes a large number of decisions about who to hire and how to spend public funds: his record shows Sadiq Khan can't make those decisions in a way that stands up for Londoners."
Mr Khan is the bookies' favourite to win the May 5 election and see off the challenge of his Tory rival Zac Goldsmith.
A spokeswoman for Mr Khan said: "Clearly these are serious issues. Shueb Salar has been suspended from Sadiq Khan's parliamentary office pending an investigation."