The United States has charged two men with conspiracy, saying they lobbied the U.S. government without disclosing the fact that they were being funded by the Pakistani government, including its spy agency.

Syed Ghulam Nabi Fai and Zaheer Ahmad, both U.S. citizens, are accused of being unregistered agents of a foreign government. Fai was arrested on Tuesday outside Washington and Ahmad is believed to be in Pakistan.

U.S. Department of Justice prosecutors says that Fai, as head of the Kashmiri American Council in Washington, took part in a “decades-long scheme” to influence the U.S. government's position on the disputed Himalayan region of Kashmir. They say his handlers in Pakistan allegedly funneled millions of dollars through the council to promote the Kashmiri cause among U.S. politicians and other decision-makers in Washington.

Prosecutors say the Kashmiri American Council is actually run by elements of the Pakistani government, including the country's military intelligence service . U.S. officials say Fai has received at least $4 million from the Pakistani government since the 1990's through Ahmad and his funding network in Pakistan.

A U.S. Federal Bureau of Investigation official, James McJunkin, said Tuesday that foreign governments who try to influence the U.S. by using unregistered agents “threaten our national security.”

Kashmir is divided between Pakistan and India and claimed in full by both. The nuclear-armed nations have fought two wars over the disputed region.