The smugglers, who were stopped wednesday at a spot off the coast of Panama, had been spotted by the intelligence services of Colombia’s anti-narcotics police, the head of that force, General Alvaro Caro, told reporters.He said Colombian authorities notified U.S. coast guard officers who carry out interdiction operations in international waters of the Pacific Ocean and the Caribbean.The Colombians will be kept in U.S. custody based on the terms of a bilateral maritime interdiction accord regarding drug smugglers detained in international waters.Caro said the speedboat apparently departed Colombia “at a point on the coast of Choco,” a northwestern province that borders Panama.The shipment has an estimated value of $55 million on the international market, according to the general.