LA PAZ, Bolivia -- Bolivian authorities discovered 3 tons of cocaine in a huge instant mashed potato shipment, netting a total of 5 tons of the drug in a historic two-day bust, officials said on Sunday.

The cocaine -- destined for Spain and valued at about $300 million -- was seized in the city of Santa Cruz, 560 miles (900km) east of La Paz, the government said.

The country's anti-narcotic special forces arrested 24 people, including one Colombian, in raids on Friday and Saturday.

A preliminary analysis of nearly 15 tons of instant mashed potatoes confiscated on Saturday showed it contained 3 tons of cocaine, said Vice-Minister Ernesto Justiniano, who directs Bolivia's anti-drug policies.

Drug traffickers had planned to send the 2 tons of cocaine seized on Friday to Madrid in a plane operated by Brazilian airline Varig, said Col. Luis Caballero, head of the special forces.

Bolivia is the world's third-largest cocaine producer after Colombia and Peru -- and it is the poorest nation in South America.

In danger of losing U.S. aid, governments since the 1990s have eradicated thousands of acres of plants in Bolivia by hacking down or uprooting plants, mostly in Chapare region, Reuters reported.

But the effort in Chapare is now in trouble. The government has faced resistance from farmers and dozens of people have died in protests in the last few years. Potent homemade mines killed two soldiers in June.