The Last Dinner Party have cancelled further tour dates “due to an unforeseen illness in the band” after an investigation into security policy at one of their gigs was launched.

The Brit-winning band, who cancelled shows in Lincoln and Cardiff this weekend, have now called off their headline tour dates in Birmingham, Nottingham, Bristol and Southampton “following medical advice”.

“We have to prioritise our health at this time,” a statement on social media said.

It comes after the band said they were “appalled and disappointed” after a Lincoln venue enforced a security policy that left fans feeling “uncomfortable and disrespected” – with audience members online suggesting male fans faced prejudice.

A statement posted on The Last Dinner Party’s social media said the band were not aware of the security policies at the show and “they would not have been implemented had we been made aware of them in advance”.

The Engine Shed, dubbed Lincolnshire’s largest live music facility, has since apologised in a statement on X, confirming it had also launched an investigation into the incident.

It said security policy was changed in response to “incidents” at a previous The Last Dinner Party gig, but that it resulted in the “unacceptable treatment of some guests” during entry.

The venue acknowledged that security procedure “fell far short of our venue entry policy, which requires all attendees to be treated equally and be subject to the same entry requirements”.

The Last Dinner Party pulled out of the Saturday gig in Lincoln at the last minute, “due to a band member unexpectedly falling ill”, the venue said at the time.

The Mercury-Prize nominated band, who also cancelled their Sunday show in Cardiff’s TramShed, have since announced further dates on their UK and Ireland tour have been called off.

“We are devastated not to be sharing these nights with you, and to have missed the shows in Lincoln and Cardiff,” a statement on the band’s social media said.

“You should all know you’ve made this the most wonderful year of our lives and we can’t thank you enough for your love and support, truly.

“TLDP is here today because of you and we want to keep touring and sharing our music with you for a long long time – but in order to do that we have to make serious decisions like these now so that our long term health doesn’t suffer.”

The Last Dinner Party are an all-female indie outfit comprising lead singer Abigail Morris, guitarist Emily Roberts, Lizzie Mayland on rhythm, bassist Georgia Davies, and Aurora Nishevci on keyboard.