Siobhan Baillie, who represents Stroud, said there were "plenty of ways to make a point about politics or governments without resorting to putting excrement in a box" outside her workplace.

In a tweet, she condemned the "nastiness" MPs face, warning that as a result "many decent people are thinking twice about standing for public office".

A spokesperson for Gloucestershire Police confirmed the incident to Sky News, saying it was reported to them shortly after 1.30pm last Wednesday.

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They force added: "Police are investigating an allegation of harassment after an offensive item was left outside of the constituency office of Stroud MP Siobhan Baillie. Enquires are continuing.

"We are taking this incident of harassment seriously and ask that anyone with information contacts Gloucestershire Constabulary through the website, quoting incident 212 of 2 November."

It is not the first time Ms Baillie has been targeted since she won the seat in 2019, having received angry messages about her taking maternity leave after the birth of her daughter in May 2020.

One constituent described it as a "dereliction of duty", while another another said: "Having a baby in not an excuse for not responding to my email."

Harriet Butcher, Ms Baillie's then senior parliamentary assistant, said at the time: "Sadly, Siobhan has received unpleasant emails, the vast majority from men who seem to think the 2010 Equality Act does not apply to a woman because she is an MP.

"It does apply and Siobhan has an absolute right enshrined in law to take maternity leave."