An Indian-origin Singaporean has been deported home from the U.S., after he had completed a jail term for offences related to trying to buy arms worth $900,000 for Sri Lanka’s outlawed separatist group LTTE.

Balraj Naidu Ragavan, 51, returned to Singapore on December 16 after serving almost four years in a U.S. prison, The Straits Times reported on Saturday.

“As a convicted felon, Naidu is prohibited from re-entering the United States,” U.S. Customs Enforcement and Removal Field Office director Simona L. Flores, said in a statement.

The businessman was extradited four years ago to face several charges in the U.S., including conspiring to export arms to the Tamil Tigers.

In April 2006, on being introduced to a U.S. undercover agent, Naidu negotiated to buy weapons worth $900,000, including grenade launchers, sniper rifles and machine guns.

One of his co-conspirators, Haniffa Osman, test fired several of the weapons in the summer of 2006 in Baltimore.

About 28 tonnes of weapons and ammunition were airlifted to the island of Guam. Osman, 62, has completed a 37-month jail sentence and testified in Naidu’s trial in 2010 before returning to Singapore.

The plan had been to offload the U.S.-made weapons in international waters off the Sri Lankan coast, so that they could be picked up by the Tigers.

But the conspirators, which included two Indonesians and a Sri Lankan, were arrested after inspecting the arms and transferring a further $450,000.