Fire broke out late Friday at a shopping mall in Malaysia's famed Petronas Twin Towers, forcing hundreds of panicked moviegoers to evacuate but causing no serious injuries, witnesses and officials said.

Fire engines, ambulances and police rushed to the scene in downtown Kuala Lumpur, where the blaze broke out in the Twin Towers' Suria shopping centre, a popular tourist spot filled with high-end boutiques and the cinema multiplex.

A security guard at the Twin Towers - the world's second tallest building - said some 500 people were evacuated when the fire broke out at about midnight (1600 GMT). Firefighters worked for 90 minutes to douse the flames.

There were no serious injuries reported, although one person was treated for smoke inhalation, an ambulance worker said.

Minor damage to cineplex

Fire brigade official Mahinder Singh told reporters that the blaze had erupted in a stairwell two floors below the Tanjong Golden Village multiplex near a restaurant, but the cause was not immediately known.

Scorched pots and pans and a metal table littered the scene, he said.

When asked how the fire began, Singh said: "That's what we want to find out - who put those things in the staircase."

The complex suffered only minor smoke and water damage, he added.

Singh refused to rule out arson, saying authorities were continuing to investigate and would question the owner of the restaurant. The official said further details would be made available on Saturday.

One moviegoer, a 29-year-old who asked only to be identified as Jevan, said smoke started appearing in the theater about 10 minutes into the film. Audience members started filing out and moved into an adjacent corridor, he said.

"We hit the alarm. It wasn't working at all, and some of the people were trying to get out through the emergency exit, but they couldn't make their way out," he said.

Patrons eventually reached the main lobby, where multiplex workers directed them to evacuate.

"We saw the smoke and just took the customers outside. We didn't see the fire," said Puspa Lata, a cinema customer relations officer.

All alarms working

Contrary to several witness accounts of malfunctioning fire alarms, Singh insisted that all alarms in the complex were working.

Security officials declared the all-clear at 2.00 am, allowing patrons to retrieve their cars from an underground parking lot.

The glass and steel Twin Towers, which mainly house corporate offices, were largely empty at the time of the fire due to the late hour. The six-level crescent-shaped Suria shopping centre forms the base of the 88-storey towers.

The 452-metre (1,483-foot) Twin Towers were the world's tallest buildings until they was upstaged by the 509-metre-high Taipei 101 in Taiwan's capital.