MIAMI — Colombia’s top anticorruption prosecutor was arrested Tuesday in his country’s capital after Drug Enforcement Administration agents in Miami said they had recorded him in South Florida at meetings where a former Colombian governor was asked to pay bribes in exchange for favorable treatment and names of witnesses.

The arrest is a blow to Colombia’s president, Juan Manuel Santos, whose conservative critics have accused his administration of mismanagement. In April, more than 10,000 people took to the streets to protest what many say is widespread graft.

The prosecutor ensnared in the latest case, Luis Gustavo Moreno Rivera, 35, is the director of the anticorruption unit of the attorney general’s office in Colombia. Mr. Moreno was under scrutiny by federal investigators in the United States because of accusations that he planned to seek a bribe from a criminal defendant while in Miami this month to deliver an anticorruption presentation to the Internal Revenue Service.

“With indignation and profound institutional pain,” the Colombian attorney general’s office said Tuesday, Mr. Moreno was held after Interpol issued a red notice “for conduct that seriously damages our institutional integrity.”