, a 21-year-old rising singing star managed by his company, were helping police with their investigations. Yeung said in the statement he was released on HK$2,000 (US$256) bail on Wednesday night.
He was ordered to report back to police next month.
Police have arrested 12 people since Friday in connection with assaults on two entertainers in February and July.
"While working in Ireland a few days ago, I learned on August 13 that our company's performer Joey Yung Cho-yee had been invited by Hong Kong police to assist in an investigation," Yeung said in his statement.
"I understood the Hong Kong police wanted to meet and discuss the case with me ... I shortened my trip and returned to Hong Kong ... so as to assist the investigation."
Yung, a teen idol and darling of advertisers, would not discuss the case when she appeared at a promotional event this week, although her publicist expressed shock at the police handling of the affair.
Police have refused to identify the entertainer who was assaulted in February.
Nine people were arrested last Friday in connection with an attack in July on another entertainer, Eric Tsang, police said.
They have not said if the two cases were related.
Tsang is a comedian best known for his flamboyance, sarcastic sense of humour and raucous laugh.
Several local entertainers have been assaulted in the past, but most usually choose not to report to police for fear of reprisals as many of the attacks are believed to involve powerful underworld groups known as triads.
Triads started weighing into the money-churning showbiz scene and infiltrating movie-sets in the early 1990s, dictating what sort of films to make and who should star in them. They are also heavily involved in movie CD piracy rackets.
Yeung runs a massive business empire through his privately held Questrel Holdings Ltd, which controls five companies whose shares are traded in Hong Kong.
They are media arm Emperor Technology Venture Ltd, property unit Emperor (China Concept) Investments Ltd, investment and trading arm Emperor International Holdings Ltd, showbiz arm Emperor Entertainment Group Ltd, and restaurant unit Global Food Culture Group Ltd.
A colourful figure, Yeung hobnobs with local celebrities and co-owns Global Food with his buddy, kungfu star Jackie Chan.
Entertainers groomed by his talent-spotting showbiz company - such as Yung and Nicholas Tse, boyfriend of pop diva Faye Wong - dominate TV, radio and newspaper advertisements.
Yeung partly owns a casino and hotel in North Korea. Located close to the border with China, it is aimed at attracting wealthy Chinese clients.
Hong Kong stars raised $36,200 for tsunami relief (2005-01-22)Photo: Joey Yung at Pop Award Ceremony (2002-04-15)HK police arrest showbiz boss in assault probe (2001-08-16)Joey's First Night Out in HK (2000-06-25)Hong Kong Pop star escapes flat fire (2000-02-28)
