All the six accused in the case were arrested last night, police said.
A fisherman was hung upside down on a fishing boat and assaulted by a group of fellow fishermen for allegedly stealing a mobile phone.
The incident took place on a fishing boat anchored at the Mangaluru fishing harbour at Bandur on December 15, but police have registered a case after a video of a group of fishermen assaulting the man accused of theft went viral.
Police have registered a case under several sections of the Indian Penal Code, including attempt to murder. All the six accused in the case were arrested last night, police said.
All the fishermen seen in the video are from Andhra Pradesh, police added.
The fisherman assaulted for allegedly stealing a cell phone has been identified as Vaila Sheenu, according to a report by news agency ANI.
The 25-second video clip shows the man hanging upside down from a hook that appears to be attached to a weighing machine. His feet are tied and he is stripped up to his waist.
The video shows other fishermen surrounding him on the fishing boat. While some of them are heard shouting at him, one man steps ahead and slaps him.
"An FIR has been registered under multiple sections of the Indian Penal Code after a few fishermen, in a video, were seen thrashing another fisherman on a fishing boat for allegedly stealing a mobile phone," Mangaluru Police Commissioner N Shashi Kumar said, according to an ANI report.
Police have now said further probe in the matter is underway.