A male elephant at a camp in Phang Nga killed its mahout by trampling him after tossing the man off yesterday.
The two tourists, still seated on the elephant's back, endured the killing and the tension filled 30 minutes that followed.
Rescuers feared the elephant could flee deep into surrounding jungle, with the two tourists on board.
Fortunately, stuck by two tanquilliser darts and then controlled by a second mahout who used a slope to jump onto the large animal's back, the ramapging elephant was eventually subdued.
Many tourists from Phuket ride elephants on the island or go north for an outing to ride in Phang Nga, where there are greater stretches of wilderness.
The Director of Livestock Phuket, Weerasit Puthipairoj, said today that male elephants sometimes went on rampages during musth, the mating season.
The vast majority of about 210 elephants used for tourist treks on Phuket at 30 camps are female, he said.
''It's accepted that mahouts with male elephants need to isolate their animals in the jungle once the telltale signs of musth approaching become apparent,'' Khun Weerasit said.
The killer elephant, Meaw, was 18 years old and possibly considered too young for musth by his mahouit, Suk Subbak, aged 60.
The pair had arrived at the Phang Nga camp two years ago from Surin province.
Rescuers urged the Russians on the enraged elephant to ''stay calm and hold tight'' during their ordeal.
While there was no law against male elephants being used in trekking business, Khun Weerasit said the mahouts had a moral obligation to isolated the beasts during musth.