This video shows a panicked swimmer, aware that the crocodile was following him, trying to make it to shore before a potential attack.

Shocked tourists can be heard on the overhanging Boca Paila bridge in Sian Ka'an as they watched the man trying to make it to safety.

One of the by-standers throws an object into the water to distract the crocodile and luckily it seems to work.

Manuel Carrera, who captured the video "not long ago", said locals didn't enter the water here for fear of enticing the male crocodile, which feeds off food left by tourists.

"Unfortunately, that crocodile already associated us with food and as the video shows the boy was saved because the crocodile is well fed and chased at a pace that allowed him to reach the shore," Mr Carrera said.