Colombian police say they have arrested a man on a list of the drug-traffickers most wanted by the US.
President Alvaro Uribe has vowed to beat "narco-traffickers"
The US says Dagoberto Florez Rios is a member of the Norte del Valle cartel, which is estimated to smuggle at least 30% of the cocaine that reaches the US.
Washington had offered $5m for information leading to the arrest.
President Alvaro Uribe has pledged to defeat "narco-traffickers", and has boosted the number of extraditions to the US since he came to power in 2002.
In a separate development, the Colombian government agreed to extradite three other drug-trafficking suspects to the US, reports say.
Efe news agency says the men are Olmedo Gil Carmona, Elias Cobos Munoz and Florentino Riviera Farfan.
Earlier this month, Colombia extradited one of the world's most notorious drug traffickers, former Cali Cartel boss Gilberto Rodriguez Orejuela.
He is wanted in the US on charges of smuggling and money-laundering.