Correa, a U.S.-educated economist who calls himself a “modern leftist,” made the remarks during a meeting with international correspondents and did not offer any more details.
“There are about 50,” he said. “What justifies that?”
“Unfortunately, these people have been infiltrated in all sectors, which scandalously seemed normal. They flew in the helicopters of the air force, of the army. It was normal for foreign soldiers to be flying with our soldiers in frontier areas.”
The U.S. Embassy’s press officer, Jeffrey Weinshenker, told The Associated Press that it had not received any notification from Ecuador’s government about the subject.
“There are about 20 military and civilians accredited before the Ecuadorean government to participate in a range of activities,” Weinshenker said. “All our activities occur with the explicit approval of Ecuadorean authorities.”
Relations between the U.S. and Ecuador have been rocky in recent years, and Correa’s government recently announced it was asking the U.S. Agency for International Development to leave, accusing it of backing the opposition.
His government also renounced eligibility for U.S. trade preferences last year when Washington was trying to pressure it into rejecting asylum for Edward Snowden, the U.S. leaker living in exile in Russia.
Correa has expelled at least three U.S. diplomats since first taking office in 2007.
The most recent was Ambassador Heather Hodges in 2011 in response to a diplomatic cable divulged by WikiLeaks in which Hodges accused a newly retired police chief of a long history of corruption and speculated that Correa was aware of it. She was later replaced.
Shortly after assuming power, Correa purged Ecuador’s military officers deemed to have close relations with U.S. counterparts. He also ended an agreement with Washington that allowed U.S. drug interdiction flights to be based at the Ecuadorean airfield in Mantua.
Correa is popular at home for his poverty-fighting programs but widely criticized for stifling civil liberties.
Associated Press writer Frank Bajak in Lima, Peru, contributed to this report.