A fire ripped through pet shops next to Bangkok's famed Chatuchak market early Tuesday, killing caged dogs, cats, birds and snakes, and damaging more than 100 stalls, police said.

The fire is believed to have started in the ornamental fish zone in Srisomrat Market, adjacent to the bigger Chatuchak, around 4:00 am (2100 GMT), according to Tivakorn Prongseng, a police inspector investigating the case.

The blaze spread to more than 100 stalls across about 1,300 square metres (14,000 square feet), he told AFP.

There were no reports of human casualties, but multiple caged animals were found dead at the market, which belongs to the State Railway of Thailand, he said.

The fire was extinguished by 6:00 am, and the cause is being investigated, Tivakorn added.

Local media reported that hundreds of pets had died in the fire, but Tivakorn said it was too early to say how many had perished.

The Bangkok Metropolitan Administration has set up a presence at the scene to gather information from affected shop owners.

Bangkok Governor Chadchart Sittipunt visited the site and said people could help affected shop owners by offering to house surviving animals.

Fires have previously damaged sections of the neighbouring, tightly packed Chatuchak market, which sells everything from antiques and electronics to dishwares and food.

The market is a top tourist draw, but also a popular shopping destination for locals.

Conservation groups have previously raised concerns about the sale of live animals in the area, with periodic raids on sellers netting endangered species.