At least 20 people were feared killed after suspected militants opened fire on tourists in India's Jammu and Kashmir territory on Tuesday, three security sources said, the worst attack on civilians in the troubled Himalayan region for years.

The region's chief minister said the attack was "much larger than anything we've seen directed at civilians in recent years".

Gunmen killed at least 24 people after opening fire on a group of tourists in Indian-administered Kashmir on Tuesday, with authorities describing the incident as a "terror attack" and the worst