RIYADH — Five persons, including two Saudis and three Syrians, were arrested with a huge cache of narcotic pills in Riyadh. They were trying to smuggle in a total of 765,000 amphetamine tablets that were hidden inside the shipment of watermelons. Maj. Muhammad Al-Nujaidi, spokesman of the General Directorate of Narcotics Control, said on Wednesday that the follow-up of security forces on gangs dealing with smuggling and the sale of drugs, targeting the security of the Kingdom and its youth, resulted in the seizure of 765,000 amphetamine tablets in Riyadh, hidden inside a shipment of watermelon. He said that all the accused were arrested, and initial legal measures had been taken against them and referred them to the Public Prosecution.