Hong Kong - British Airways has banned its staff from drinking at a popular Hong Kong bar after stewardesses were slipped a date-rape drug while drinking there, a media report says.

Hong Kong under a pall of pollution. British Airways has banned its staff from drinking at a popular Hong Kong bar after stewardesses were slipped a date-rape drug while drinking there, a media report says. [AFP]

The ban follows a warning to the British flag-carrier's 13,000 staff in November about the threat of drinks being spiked with the tranquilliser Rohypnol while drinking off-duty in unsavoury bars.

Hong Kong's Sunday Morning Post, citing sources, said BA was concerned about one popular unnamed bar in the seedy Wan Chai district following complaints from four stewardesses that they felt unwell after visiting it in the past year.

"We are undertaking an investigation following a number of reports of crew feeling unwell after visiting the bar," BA told the Post from London. "We have advised our crew to avoid visiting the bar."

Sources told the Post the four had found they'd been drugged with Rohypnol, a tranquilliser prescribed to insomniacs but which has often been used by rapists to snare their victims.

The infamous Wan Chai harbourside district was Hong Kong's centre of vice and crime when it was a major docking area for British and later US naval port calls.

While the Hong Kong government has since tried to clean the area up, its handful of remaining go-go bars remain a reminder of its seamier past.