Thousands of people formed a 500 km-long human chain from Kerala to Tamil Nadu on April 28 to demand better security for Indian fishermen. They demanded improvements in safety against a backdrop of recurring attacks and deaths of Indian fishermen hit by passing vessels. The passing ships sail within 20 nautical miles from the Indian coast to avoid piracy threats and this results in collisions with fishing boats, said T Peter, convener of Kerala Independent Fish Workers Federation and one of the organizers of the event.