This is the heroic moment a youngster swam through a river to save a fish trapped in a plastic bag.

Video shows the selfless local paddling toward the fish suffocating inside the plastic rubbish in Samut Prakan province, Thailand, on March 31.

His family applauded him as he set the fish free into the water.

The Good Samaritan said: 'I felt bad because it was stuck and flailing around in the river. I didn't want it to die so I decided to help it.'

Thailand has become notorious for its polluted rivers and canals, with plastic pollution posing a threat to both the environment and public health.

Fish, birds, and other wildlife can ingest or become entangled in plastic debris, leading to injury, starvation, or death.