Colombia's President Ivan Duque has declared the "end" of the Gulf Clan drug cartel, formerly the country's largest, after the capture of its leader and dozens of other members.

Dairo Antonio Usuga, also known as Otoniel, was arrested on 23 October in a raid involving 500 police and military personnel.

The 50-year-old is waiting to be extradited on drug trafficking charges to the United States, which had offered a $5 million reward for his capture.

In recent days, authorities arrested another 90 suspected members of Colombia's largest cocaine cartel, which operates in concert with Mexican drug gangs in almost 30 countries.

"The Gulf Clan as a monolithic structure has reached its end," Mr Duque told Colmundo Radio.

"The chain of command was completely broken and it was highly concentrated in the person of 'Otoniel.'"

The president also warned remaining members of the group to "surrender, or we will hit them hard."

Dairo Antonio Usuga after his capture

Otoniel, the subject of 26 Colombian arrest warrants for murder, terrorism, child recruitment and kidnapping, among other crimes, was arrested in the country's northwestern forests, where he also fought with far-right paramilitary forces.

Four soldiers have been killed in what authorities said was retaliation for the crackdown on the Gulf Clan.

Police say the group was responsible for a third of all cocaine exports from Colombia - the world's biggest producer of the drug.

The United States is the main destination.

The Indepaz research institute estimates that the Clan has a force of some 1,600 men, while authorities say it has about 3,800 fighters and members.

Colombia is officially at peace after signing a pact with the FARC guerilla group in 2016 to end more than half-a-century of armed conflict.

But it has seen a flareup of violence in recent months due to fighting over territory and resources by dissident guerillas, the ELN rebel group, paramilitary forces and drug cartels.