From the facility, located somewhere in the United States, the C.I.A. has stockpiled and distributed untraceable weapons linked to preparations for the Bay of Pigs invasion and the arming of rebels and resistance fighters from Angola to Nicaragua to Afghanistan.
Yet despite hints that “Midwest” was not actually where it was located, the secrecy surrounding the C.I.A. armory has survived generations of investigations. In a 2007 essay on the 20th anniversary of the Iran-contra affair, for example, a congressional investigator noted that the facility where the C.I.A. had handled missiles bound for Iran remained classified even as other “incredible things were unveiled during the hearings.”
But three years ago, it became public that the C.I.A. had some kind of secret location at Camp Stanley, an Army weapons depot just north of San Antonio and the former Kelly Air Force Base, though its purpose was unclear. And now, a retired C.I.A. analyst, Allen Thomson, has assembled a mosaic of documentation suggesting that it is most likely the home of Midwest Depot.
In December, he quietly posted his research, which he has updated several times with additional clues, on the website of the Federation of American Scientists. In an email exchange, Mr. Thomson argued that the Midwest Depot’s history should be scrutinized.
“I have worried about the extent to which the U.S. has spread small arms around over the decades to various parties it supported,” he said. “Such weapons are pretty durable and, after the cause du jour passed, where did they go? To be a little dramatic about it, how many of those AK-47s and RPG-7s we see Islamists waving around today passed through the Midwest Depot on their way to freedom fighters in past decades?”
Spokesmen for the Pentagon and the C.I.A. declined to comment. A public affairs officer for Camp Stanley said its mission was to be a weapons storage and testing facility for the military.
There is no outward indication of what would be one of the C.I.A.’s three known facilities in the United States, along with its headquarters in Langley, Va., and Camp Peary, a military base near Williamsburg, Va., known by its code name, “The Farm,” that is believed to be used for training. Camp Stanley has a low-key gated entrance, and a few nondescript warehouses are visible from its perimeter fence. Rows of bunkers are nestled deeper into the base, according to satellite images.
The mayor of the nearby town of Boerne, Tex., Mike Schultz, said he knew nothing of any C.I.A. presence at Camp Stanley. Henry Cisneros, a former mayor of San Antonio who served as secretary of Housing and Urban Development, also said he had never heard speculation about a C.I.A. role there.
The existence of a C.I.A. facility at Camp Stanley first surfaced in 2011 because of lawsuits brought by Kevin Shipp, a C.I.A. official who had lived with his family in a government-owned house there a decade earlier. His family grew severely ill from exposure to a toxin, possibly from mold in the house, though the base is environmentally contaminated. Their possessions were destroyed.
Mr. Shipp also wrote a memoir, but a C.I.A. pre-publication review board blacked out large parts about his family’s experiences. His son, Joel Shipp, noting that he signed no confidentiality agreement, said he was writing his own memoir and wanted to sell the movie rights. He said he still suffered health problems from his teenage years, confirming that the C.I.A. had sent his family to Camp Stanley, which he called “a secret base which had been used for illegal arms running and chemical weapons storage.”
The 2011 Times article caught the eye of Mr. Thomson, who worked for the C.I.A. from 1972 to 1985 and now lives in San Antonio. He searched through declassified documents and old articles, accumulating clues.
Several of the documents he found traced Midwest Depot’s role without identifying its location, including a 1967 C.I.A. memo linking it to paramilitary training of Cuban exiles before the 1961 Bay of Pigs invasion, and a 1987 State Department memo showing that equipment bound for the Nicaraguan contras passed through it.
The Times separately identified a 1963 C.I.A. memo discussing 300 tons of C-4 plastic explosives that were available in the “Midwest Depot stocks.” There were no restrictions on its use “because the items have world-wide distribution and are consequently deniable.”
In a 2009 interview, a former C.I.A. logistics officer said AK-47 rifles sent to the Northern Alliance after the Sept. 11, 2001, attacks came from the C.I.A.’s Midwest Depot stockpiles. Arms funneled to anti-Marxist fighters in the Angolan civil war in the 1970s did, too, another former C.I.A. official said this month, while emphasizing that he was never told its location.
But Mr. Thomson, who said he had not been read into classified information about Midwest Depot’s location when he worked at the C.I.A., identified a series of references in old news accounts, books and interviews placing a covert weapons depot near San Antonio.
And he found an explicit reference in a 1986 memo by Col. Oliver North, a chief figure in the Iran-contra affair. It said the C.I.A. would truck missiles bound for Iran from a military arsenal “to Midwest Depot, Texas,” for preparation, then fly them out of Kelly Air Force Base. Connecting Midwest Depot to yet another historical episode, it added that some missiles would go to “Afghan resistance” fighters battling the Soviets.
Camp Stanley has recently undergone a building boom of new warehouses. A March 2010 solicitation for environmental cleanup emphasized that workers needed security clearances. “The installation stores large quantities of arms and ammunition and has sensitive missions, thus access to the installation and security clearance requirements for long-term personnel are much more restrictive than most military installations,” it said.
Just last July, according to another document Mr. Thomson spotted, the Army sought to purchase two million rounds of ammunition of the caliber that fits AK-47 rifles, which American soldiers do not use. The delivery address: Camp Stanley.