Two people have been arrested over a series of threatening social media posts directed at MPs, including one sent to Anna Soubry which read “REMEMBER WHAT HAPPENED TO JO COX SO BE CAREFUL”.

The pair are believed to run a Twitter account named Sheffield and Yorkshire Direct Action Brexit Group, which also sent a photo of a crossbow with the caption: “We are ready for civil war... are you?”

The tweet was sent to five Remainer MPs: Ms Soubry, Chuka Umunna, David Lammy, Angela Smith and Sarah Wollaston.

A 40-year-old man and 33-year-old woman were arrested in Sheffield after the social media posts were reported to police earlier this week, South Yorkshire Police said.

The pair have since been released on bail.

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Ms Cox was the MP for Batley and Spen who was murdered in June 2016.

The Twitter page’s biography section reads: “We need to leave the EU and the politicians are not listening.

“We want to start a movement to help as many people as possible have their voice heard. Help us.”

It comes as Ms Soubry voiced fresh security concerns, saying one entrance to Parliament poses a “serious threat to safety”.

Ms Soubry, who left the Conservatives to join the Independent Group over Brexit, said staff were being “intimidated” near the Palace of Westminster.

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