Two teenagers were in police custody in northwestern France on Monday, a day after an 11-year-old boy was found dead with a wet towel tied around his neck, prosecutors said.The boy was found on the banks of the Vilaine river in the northwestern city of Rennes with a wet bath towel tied tightly around his neck, prosecutors said on Sunday.On Monday, a 16-year-old boy was detained at his home, while a 15-year-old girl was detained after presenting herself to police, Rennes prosecutor Frederic...