Fans of the X Factor will be in for yet another treat if they head to the Sundown Festival in Norfolk this summer after boy-band Union J were confirmed.

The four-piece band, who were semi-finalists on last year's hit ITV1 show, have been confirmed as additional main stage guest performers at this year's festival at the Norfolk Showground.

It means the band, comprising Josh Cuthbert, Jamie 'JJ' Hamblett, James 'Jaymi' Hensley and George Shelley, will be performing on the same bill as X Factor winner James Arthur who was confirmed as an act earlier this month and former X Factor contestants JLS.

Together they join the likes of weekend headliners Jessie J, Example and DJ Fresh at the festival which takes place on Saturday, August 31 and Sunday, September 1.

Union J, who became a four-piece during the 2012 X Factor series when then soloist Shelley joined the others, signed a record deal with Sony Music last month and are expected to release their debut single in June.

Sundown Festival spokesperson, Dion Clements said: 'Union J are very possibly one of the most popular and hotly anticipated X Factor acts not to have reached the final, so we're very pleased to have them performing at Sundown.'

Set to perform on the Sunday of Sundown, Union J joins the previously confirmed line-up of main stage weekend headliners, with Rinse and Hospitality hosting Stage 2

Middlesborough-born singer James Arthur was praised on the X Factor for his notable blend of pop, rap and freestyle performances, and eventually went on to win the series.

The release of his debut single, Impossible, saw him go straight to number one in the UK Singles Chart and the single has since become the best-selling X Factor UK winners single and has also been nominated for Best British Single at this year's Brit Awards.

Tickets are on sale now for Sundown Festival, which will take place at the Norfolk Showground on Saturday 31 August & Sunday 1 September. For more information, or to book tickets for the event, visit www.nationalboxoffice.co.uk, or call 0871 224 1112 / 1113.