"All 35 people arrested from aboard the American ship have been sentenced to five- year imprisonment and asked to pay fine of Rs.3,000 each. Eight people charged with supplying diesel for the ship were acquitted," additional public prosecutor K. Sivakumar told IANS on phone from Tuticorin in Tamil Nadu.
The Coast Guard said the crew included eight Indians and two Ukrainians while six Britishers, 14 Estonians, one Ukrainian and four Indians were among the security guards on the ship.
They were arrested when the ship flying West African country Sierra Leone's flag was found moving around 15 nautical miles from Tuticorin port in October 2013 with arms and ammunition without valid authorisation or documents.
The state police had alleged that the ship had obtained 1,500 litres of diesel illegally from private sources.
The ship belonged to US company AdvanFort that specialises in providing maritime security against pirates.
After the Indian Coast Guard escorted the ship to Tuticorin port, those aboard were questioned by officials of different security departments and agencies.
In 2014, the Madras High Court dismissed the charges against the crew and armed guards but reaffirmed charges against the ship's captain and the fuel vendors.
On an appeal by the Tamil Nadu Police, the Supreme Court in 2015 set aside the high court judgment and ordered a trial by the Tuticorin sessions court.