Flash floods swept through a popular elephant sanctuary in northern Thailand on Thursday, forcing the evacuation of about 100 elephants and trapping dozens of tourists, amid urgent pleas for help.

Authorities and conservationists are rushing to rescue elephants, pigs and buffaloes from flash flooding in Thailand's northern Chiang Mai province, a senior official said on Friday.

Flash floods in the north led to the evacuation of 100 elephants to higher ground, though some were swept away and others left stranded on a patch of land reachable only by boat.