Security concerns over a possible terrorist attack during the Beijing Olympics spread to Hong Kong on Monday, with a top immigration official warning the city's hosting of Olympics equestrian events could be targeted.

"Intelligence reports suggest to us that there are some people who will come to sabotage Olympics events including equestrian events," said Simon Peh, Hong Kong's director of immigration, in an interview to a select group of local media.

"Of course this kind of intelligence will continually change ... right now the main individuals who might sabotage the event are terrorists," Peh added, without giving any specifics on where these terrorists might come from or their affiliation.

The head of Interpol, Ronald Noble, said in April there was a "real possibility" that the Beijing Olympics would be targeted by terrorists, but this was the first time that specific intelligence had suggested a possible security threat involving Hong Kong.

The former British colony will have a fringe Olympics role this August, hosting equestrian events on behalf of Beijing after the capital city failed to set up a disease-free zone for horses.

Hong Kong's police said in an emailed response to Reuters that the terrorist threat level was "moderate" during the Olympic equestrian event and it would beef up security at the airport and other critical infrastructure during this time.

The statement also sought to downplay Peh's comments, saying that, while there was a general inherent risk in hosting any large Olympic event, "there is currently no specific intelligence to suggest that Hong Kong is likely to be a target for terrorism."

INTERNAL THREAT?

Noble of Interpol has said that foreign militants would find it very difficult to operate in China, and Beijing was more concerned about a terrorist threat coming from inside the country.

China has accused Uighur militants in the far western, mainly Muslim region of Xinjiang of plotting attacks with al Qaeda's support to help achieve their goal of establishing an independent country called East Turkistan.

The international leg of the Olympic torch relay has been dogged by pro-Tibet and anti-China protests, following unrest in Tibet last month in which China says about 20 people died.

Hong Kong too, saw protests during its May running of the torch with a handful of activists denied entry to the city and deported, and Peh said this might happen again in August.

Security has been an ever-present worry at the Olympic Games since 11 Israelis died in Munich in 1972 after Palestinian gunmen took them hostage and German authorities botched a rescue attempt.

Security was a huge concern when the United States staged the Salt Lake City Winter Olympics in early 2002, just five months after al Qaeda's Sept. 11 attacks on New York and Washington.

Two years later, Greece spent some $1.8 billion to protect the Athens Summer Games in 2004.