GUATEMALA CITY, Guatemala (CNN) - Guatemalan authorities, together with the U.S. Drug Enforcement Administration, captured a makeshift submarine carrying thousands of kilos of cocaine, a government official said Thursday.

The amount of cocaine on the ship was unconfirmed, but local reports estimated the illicit cargo at 10,000 kilograms (approximately 22,000 pounds). If so, it would be the largest drug bust by Guatemalan authorities.

Colombian officials alerted the Guatemalans and Americans about the cocaine-laden submarine, Guatemalan Interior Minister Raul Velasquez told CNN en Español. A DEA vessel in the Pacific Ocean heading elsewhere was diverted to interdict the submarine Wednesday night. Authorities caught up to the vessel in international waters off the Guatemalan coast, authorities said.

Three Colombians and one Mexican national onboard the submarine were arrested, Velasquez said. The names of the suspects and exact amount of cocaine were unknown because the DEA ship ran out of fuel, resulting in a delay coming in to port.

Guatemalan officials, possibly including President Alvaro Colom, planned to meet the DEA ship and its cargo when it finally arrives Friday, Velasquez said.

U.S. officials estimate "drug subs" now transport about one-third of all cocaine that moves by sea from South America to the United States. The makeshift vessels come in several forms and are built of fiberglass, wood and steel in the swamps along the west coast of Colombia, under the cover of heavy foliage, according to the U.S. Coast Guard.

–Journalist Alexia Rios contributed to this report for CNN.