Mercury Prize-winning musician PJ Harvey has started recording her new album under the watchful eyes of some of her most devoted fans as part of a new art installation.

The musician will spend four weeks working on her ninth album with her band and production team behind one-way-mirrored glass at Somerset House in London.

Her last release, 2011's Let England Shake, a collection of songs inspired by conflicts around the world, was her second Mercury winner, taking the prize for the best album of the year a decade after Stories From The City, Stories From The Sea was honoured.

Organisers were staying tight-lipped about the event and fans had to hand over their mobile phones before attending the Recording In Progress project.

Writing in Time Out, Martin Coomer described watching her and long-term collaborator Flood deep in conversation in a "conventional" studio set-up before she started singing and "something miraculous happens".

He said: "Polly writes something down, puts on headphones, takes a sip of water and launches into the refrain of a beautiful new song, recognisably from the same mould as the war-scarred soundscapes of Let England Shake."

All the tickets, which cost up to £15 for 45-minute slots, sold out soon after the event was announced.

The project is being presented by art-commissioning organisation Artangel and Somerset House and runs to February 14.

Harvey was awarded an MBE for her services to music in 2013.