ASPEN, Colo. — A military human intelligence organization that has faced headwinds in recent years is still growing in size, the Pentagon’s former intelligence chief said on Thursday.

Michael Vickers, until recently the undersecretary of defense for intelligence, said that the Defense Clandestine Service is still expanding and will continue to work alongside the military and other agencies in national intelligence-gathering efforts. He said the agency would be crucial in the wide-ranging fights the U.S. faces.

“It's growing,” Vickers said at the Aspen Security Forum, answering a reporter’s question. “It’s an important initiative in terms of human intelligence, particularly important in this world against the range of challenges you describe, and the Department of Defense and our military have something to contribute to the overall national effort.”

At its creation, the Defense Clandestine Service was meant to become an important component of human intelligence gathering within the military realm. Its size and capabilities were to match those of the CIA, the country’s main human intelligence-gathering organization.

As DIA director, Lt. Gen. Michael Flynn fought to make space for the DCS. But after facing immense opposition from lawmakers and intelligence agency officials, the plan was eventually scaled back, the Washington Post reported in November 2014.

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Vickers said that the DCS would be a complement to other agencies. “I would add: it’s a junior partner, it’s not rivaling the size of the CIA, but it’s important,” Vickers said. “We’ve had strong support from the CIA and DNI in this effort.”