A large amount of narcotics was discovered on a sail boat in a police and customs raid in St George's this afternoon.A 24-year-old Latvian man was arrested following the search at McCallan's Wharf, near Tiger Bay.Police spokesman Dwayne Caines said a joint police and customs investigation has been launched but would not reveal any further details of the seizure.A handful of officers and a police sniffer dog could be seen at the scene at around 5pm.