The first footage of an incredibly rare female tiger and her cubs have been captured by a camera trap deep in the Sumatran jungle, say researchers.
The big cat family triggered the infrared video camera after the curious hunters stopped to sniff and check out the trap.
A young Sumatran tiger is filmed on a balmy hot day by a camera trap installed by WWF in central Sumatra
The researchers say the footage gives them a unique insight into the elusive tigers' behaviour and also helps them to identify individual animals.
There are as few as 400 Sumatran tigers left in the wild and they are under relentless pressure from poaching and clearing of their habitat.
Leader of WWF-Indonesia's Sumatran tiger research team, Karmila Parakkasi, said: 'We are very concerned because the territory of this tigress and its cubs is being rapidly cleared by two global paper companies, palm oil plantations, encroachers, and illegal loggers.'
WWF-Indonesia's Forest Programme Director, Ian Kosasih, added: 'When these cubs are old enough to leave their mother they will have to find their own territory.
'Where will they go? As tiger habitat has shrunk with so much of the surrounding area having been cleared, the tigers will have a very hard time avoiding encounters with people. That will then be very dangerous for everyone involved.'
In addition to the tigress and cubs' footage, the video camera also captured images of a male Sumatran tiger and its prey, wild boar and deer, as well as many other species such as tapirs, macaques, porcupines and civets.
Time for my close-up: The two curious tiger cubs explore the clearing. There are only 400 of these big cats left in the wild
They are hoping to secure high-level political commitment at a Heads of State Tiger Summit to be hosted by Prime Minister Vladimir Putin in Russia later this year.
'We want to change the course of tiger conservation,' said Mike Baltzer, leader of WWF's global Tiger Initiative.
'It's not just about saving the tiger from extinction, but about doubling their number by 2022.'
The tigress was captured at night on a still camera, before she and her cubs were shot in video footage
