Boston (AP): The Indian-origin chief engineer of a Panama-registered container ship who oversaw the illegal dumping of tonnes of oily sludge into the ocean was sentenced by a federal court to two months in prison.

Mani Singh, 58, was also ordered by district court judge Patti B. Saris to pay $ 3,500 in fines. He had pleaded guilty in December.

MSC Elena, a 30,971-tonne vessel operated by MSC Ship Management Ltd of Hong Kong, made regular trips between European and US ports, including Boston, federal prosecutors said. The company pleaded guilty and agreed to pay a $10.5-million fine, the largest in a case involving deliberate pollution from a single vessel, and the largest fine paid by a defendant in an environmental case in Massachusetts, the US attorney’s office said.

The ship discharged about 40 tons of oily sludge during a five-month period in 2004 by using a specially fitted steel pipe to bypass required pollution prevention equipment.

The coast guard had discovered the bypass pipe during a routine inspection in Boston harbour in May 2005.