Rabat - Thirteen Spanish citizens of Moroccan origin have been arrested over a record seizure of cocaine in the North African country, the authorities said on Wednesday. Police on Monday seized over 2.5 tons of the drug, with a street value of hundreds of millions of dollars, that investigators believe landed by boat in the far south of the country from Venezuela and was destined for distribution in Europe or the United Arab Emirates. The suspected masterminds of the operation are two Dutch citizens of Moroccan origin who are currently serving jail sentences over a 2014 drug haul in Marrakesh, said Abdelhak Khiam, the head of the country's Central Bureau of Judicial Investigations. "The networks of the South American drug cartels are currently trying to make use of the African route, via the countries south of Sahara where there is little control," he told a news conference. Investigators showed off the roughly 2 500 packages of cocaine seized in the raid following some an operation by the security forces that involved some three years' of surveillance. Along with the cocaine the authorities also seized about 100kg of hashish and ecstasy tablets, cash, weapons and mobile phones.Part of the drug stash was hidden in a vehicle while the rest was stored in two farms.Over the past decade South American cartels have expanded their network of smuggling routes to the lucrative markets in Europe, landing some shipments in West Africa and moving them by land northwards.