BOGOTA, Colombia — Authorities in Colombia have seized 12 tons of cocaine worth an estimated $360 million in what President Juan Manuel Santos is describing as the nation’s largest drug bust.

Four hundred anti-narcotics officers seized the cocaine in four simultaneous operations at Colombian farms where the drugs were buried underground and covered with banana leaves.

Officials say the cocaine belonged to the Clan del Golfo, an illegal armed group that has sought to take over drug trafficking operations in zones previously occupied by the Revolutionary Armed Forces of Colombia, or FARC.

FARC rebels reached a peace agreement with the government last year that includes provisions to reduce coca production through voluntary and forced eradication.

The United Nations and the White House say coca and cocaine production surged last year in Colombia.