King credited the Secret Service director for acting quickly to remove the agents in question and replace them before Obama's arrival.
A hotel employee, speaking on the condition of anonymity for fear of losing his job, said the agents arrived at the beachfront hotel about a week ago and said the agents left the hotel Thursday, a day before Obama and other regional leaders arrived for the weekend summit.
Three waiters interviewed by the AP at the hotel described the agents as drinking heavily during their stay.
On Friday, the hotel began filling up with the delegations of some of the more than 30 countries whose leaders are convening for the weekend Summit of the Americas.
The hotel's public relations director, Ana Beatriz Angel, refused to comment on the incident, which she said "concerns only and exclusively the U.S. government."
On the steamy streets of Cartagena, a resort city with a teeming prostitution trade, there was condemnation for the Secret Service agents for what residents saw as abusing their station and dishonoring their country.
Edwin Yepes, a souvenir vendor, said "they are supposed to come here and set an example. We are an inferior culture, and so it's better if they don't come than if they damage our image of them."
Associated Press writers Ken Thomas and Ben Feller in Washington, Frank Bajak and Pedro Mendoza in Cartagena and Jennifer Kay in Miami contributed to this story.
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