They say the government conducted secret experiments that exposed thousands of troops to dangerous chemicals and mind-altering drugs.
The experiments were conducted during the Cold War era. The program, reportedly started in the early 1950's, continued through the mid 70's.
Those who participated say they never knew they would be human guinea pigs for the dangerous experiments.
Attorneys for the Vietnam veterans estimate about 7,000 troops were subjected to the secret experiments under a program codenamed "MKUltra."
"I had injections that were... The syringes were the size that you would use on a cow," described Eric Muth.
Frank Rochelle was a 19-year old draftee. He says he was given hallucinogenic drugs.
"I saw animals coming out of the wall. My skin, the freckles, now I understand, the freckles appeared to be bugs under my skin," he recalled.
Their lawyers say most of the tests were conducted at Fort Detrick, Maryland and Edgewood Arsenal, which no longer exists.
"Nerve gas, sarin gas, all kinds of toxic substances were sprayed in their face and injected into their veins," said Gordon Erspamer with Morrison & Foerster Law Firm.
Many of the drugs are still a mystery because they were identified only by numbers. The lawsuit says some of the chemical and biological substances were implanted into their bodies.
"They tested animals with the same apparatus I was required to breathe into," said Rochelle.
Muth and Rochelle say the army told them the experiments were to test gas masks and protective clothing in the event of chemical warfare.
They were promised perks if they volunteered.
"Four-day work weeks, good chow, as we called it, and being able to wear civilian clothes a lot," Rochelle recalled.
Their lawyer says they all signed secrecy oaths.
"If they ever spoke to anyone about these tests, they would be court-martialed and sent to the brig," said Erspamer.
Rochelle says many of the vets are dying. If they do not get justice now, they will never get it.
"It's about us because - it's about the guys who are left, the guys who are still living - who need health care," Rochelle said sobbingly.
The CIA, Defense Department and the U.S. Army told ABC7 they could not comment on pending litigation. But, the CIA says the program has already been "thoroughly investigated" in the past.
