The incident occurred this morning when Shabbaz Ali, along with 11 other boys arrived at Manginapudi beach to participate in a festival observed by Muslims, Machilipatnam (rural) Circle Inspector (CI) A N Narasimha Murthy said.
The boy waded further into the sea and got swept away by the waves, he said, adding the other boys tried to rescue him.
The matter was informed to the police, who launched a search operation with the help of marine police and divers, but the body could not be found, he said.