A fire on a music stage which spread into a crowd of spectators at a Taiwan water park, has left more than 500 people injured, including eight in critical condition, authorities say.

At least five people including park workers and technicians were arrested on Sunday in connection with the accident, according to the South China Morning Post. They may face charges of professional negligence causing serious injuries and endangering the public, police told Taiwan's Central News Agency.

"They will be transferred to prosecutors for further investigation on charges of offences against public safety and negligence of duties that caused severe injuries," Yen Po-ren, New Taipei police spokesman, was quoted by AFP news agency as saying.

The fire was sparked by an accidental explosion on Saturday of a coloured theatrical powder thrown from the stage in front of about 1,000 people, fire department officials and local media said.

About 1,000 spectators had been at the Color Play Asia event at the Formosa Fun Coast water park, just outside the capital Taipei, according to officials.

The powder for the one-time event ignited along the ground, mainly burning people's lower bodies, said Wang Wei-sheng, a liaison with the New Taipei City fire department command centre.

"Our initial understanding is this explosion and fire ... was caused by the powder spray. It could have been due to the heat of the lights on the stage," said a spokesperson for the New Taipei City fire department.

Lee Lih-jong, deputy chief of the health bureau of the New Taipei City government, said 509 people had been injured, with 188 of them seriously hurt.

The fire was quickly extinguished, according to authorities.

Running and screaming

Footage on the Apple Daily newspaper website showed crowds dancing as music played and clouds of powder being sprayed out which suddenly turned into a blaze that engulfed the spectators.

People were shown running for their lives, screaming, as they were overtaken by flames. Some were dressed only in swimwear and covered in the coloured powder.

Victims were carried away on rubber rings and inflatable dinghies as friends desperately tried to get them out.

About 1,000 spectators had been at the event at the Formosa Fun Coast water park when the fire started on Saturday [AP]

Bystanders poured bottles of water on the scorched skin of the injured. Trails of bloody footprints leading away from the stage remained, an AFP reporter at the scene said.

The severely wounded are being treated in intensive care units at 37 different hospitals.

"The reason why the burns were so severe was that in addition to burns to the skin, there were also injuries caused by burns to the respiratory organs from the large amount of colour powder inhaled," the health bureau's Lee told AFP.

"The next 24 hours will be critical for those severely injured."

Lee said that details of the ages of the victims were not yet available, "but all looked very young, in their 20s or even younger".

Media reports said some victims had suffered burns to more than 40 percent of their bodies.

Media reports say some victims of Saturday's fire have suffered burns to more than 40 percent of their bodies [Reuters]

Officials said that ambulances had found it difficult to get near the site and had to send in emergency workers with stretchers.

Mao Chih-kuo, Taiwan prime minister, announced a ban on Sunday on parties that use flammable coloured powder, while New Taipei mayor Eric Chu has ordered the park to shut down during the investigation.

Source: Agencies