Last night's open dress rehearsal of Sylvia at the Old Vic was brought to an abrupt end last night after one of the cast members was taken unwell.

The first preview was changed into an open dress rehearsal yesterday after Matthew Warchus released a statement citing the difficulties of the scale of the endeavour of a new musical.

An eye witness at the open dress told WhatsOnStage that cast member Genesis Lynea, who is playing Sylvia Pankhurst, was taken ill during the performance.

Director and choreographer Kate Prince then came on to apologise, saying that Lynea had been determined to come on even though she felt unwell.

The Old Vic said today: "Unfortunately last night's open dress rehearsal of Sylvia was stopped at the beginning of act two due to a member of the cast being taken unwell. The safety and well-being of our cast is of the upmost importance and therefore tonight's performance of Sylvia has been cancelled. We apologise unreservedly to all our patrons affected by this and thank audiences for their understanding and support.

"The Old Vic is contacting patrons as soon as possible to exchange their tickets or to arrange a refund. All patrons who attended yesterday's open dress rehearsal were offered refunds and the option to rebook for another performance prior to the show due to the change from first preview to open dress rehearsal."

The opening night for Sylvia has also been postponed from 11 September to 17 September "to allow more time to work on and nurture this ambitious new piece of work".

The musical stars Beverley Knight, Izuka Hoyle and combines hip hop, dance, soul and funk to tell the story of the women's suffrage movement.