WASHINGTON (AP) — An Afghan man who authorities say was one of the largest heroin traffickers in the world and who used proceeds of his drug sales to support the Taliban insurgency was sentenced Tuesday to life in prison.

Haji Bagcho, who manufactured heroin in secret laboratories along Afghanistan's border with Pakistan and sent heroin to more than 20 countries, was returned to the United States in 2009 to face charges following a yearslong investigation by Afghan and American authorities.

Bagcho was convicted in March of conspiracy, distributing heroin for importation into the United States and narco-terrorism. An earlier trial last fall ended with a hung jury.

At his sentencing hearing in federal court in Washington, Bagcho proclaimed his innocence in a long and rambling statement made through an interpreter.

His lawyers acknowledged their client's crimes were serious but urged a judge to sentence him to 20 years — the minimum possible sentence — saying Bagcho is at least 70 years old and in failing health. Prosecutors asked for a maximum sentence of life in prison.

A ledger of drug sales uncovered during the investigation showed that Bagcho was responsible for trafficking more than 1230,000 kilograms of heroin in 2006 alone. He also gave some of his proceeds to high-level Taliban officials so they could fund their insurgency against the Afghan government.

"It can be fairly said that the defendant is perhaps the largest drug trafficker by volume, and certainly the largest drug trafficker by share of global production, ever brought to justice in the United States," prosecutors wrote in a sentencing memorandum.

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