British rock band TTNG have been detained in Hong Kong over alleged visa offences. Police have arrested seven people – including the music group – for visa violations after raiding a concert at Hidden Agenda, the Kwun Tong livehouse, on Sunday night (7 May).

A post shared on Hidden Agenda's Facebook page claims that police and immigration officers on the scene said that the musicians were hired as "illegal immigrants" after "issues" with their visas.

It reads: "During tonight's show with THIS TOWN NEEDS GUNS (UK), HA was alleged by the Immigration Dept (I.D) to have hired illegal immigrants to perform amid allegations that there were some issues with the band's visa."

It added: "Authorities from the I.D tried to use force to arrest HA founder, HUI CHUNG WO. Wo was hurt during their action. Soon, police arrived claiming there was a fight," it added.

Concertgoers wrote online that two plain-clothes officers attended the concert to prove that the band performed despite having visa issues. The police then revealed their identities, arrested the musicians and a fight broke out between the police, staff and crowd, they wrote.

It has also been reported that, after receiving a call about the fight, more police officers armed with riot shields and dogs arrived at the livehouse, which has struggled with licencing issues, according to the BBC.

All three members of TTNG and a US band named Mylets were arrested on suspicion of violating the terms of their visas. They were released in the early hours of today (8 May) and are required to report back to the Immigration Department's Kowloon Bay office by the afternoon.

TTNG and Mylets were in the middle of a tour of Asia with upcoming dates on Tuesday in Guangzhou, followed by concerts in Beijing and Shanghai.

Who are TTNG?

TTNG – full name This Town Needs Guns – are a three-piece indie band made up of Tim Collis, Chris Collis and Henry Tremain.

They are from Oxford and formed in 2004, and are currently signed to the American label Sargent House Records. Their debut full-length album, Animals, was released in the UK in October 2008 and shortly after in the US.

The band has experienced numerous departures and went from being a four-piece to a trio, with Tremain on lead vocals, Tim Collis on guitar and his brother Chris Collis on drums. They released their second album, 13.0.0.0.0, in January 2013, third album named Disappointment Island last year, and have 9,4000 followers on Twitter.

The Sydney Morning Herald once described the band's music as having "intricate pop guitar work, with a touch of jazz and Spanish influences". It is also known that they cite influences from bands including Owls, American Football and Make Believe.

They have stated that their band name was ironic because guns are hardly present in their home town of Oxford and the UK in general.