Kolkata, Feb 13 (IANS): A district court in West Bengal's North 24 Parganas Friday sentenced, to life imprisonment, three youths convicted of killing teenager Rajib Das, when he tried to resist their attempts to outrage the modesty of his sister and drag her away four years back.

The three accused - Mithun Das, Manojit Biswas and Biswanath Chatterjee - were declared guilty by Additional District and Sessions Judge, Barasat, Prabir Kumar MishraThursday.

The 16-year-old Das, who was to appear for his secondary examination in a few days, was mercilessly beaten up and fatally stabbed by the trio near the Barasat railway station around 11 pm on Feb 14, 2011.

The judge Friday pronounced the same punishment for the three accused. They were sentenced to life imprisonment for murder under section 302 of the Indian Penal Code read with section 34 (common intent), besides being fined Rs.10,000. In default, there would be a further five year jail term.

The judge also sentenced them a two year sentence under section 354 (assault or use of criminal force to a woman with intent to outrage her modesty) and imposed a fine of Rs.3,000. In default, there would be an additional one year jail sentence.

The trio was also sentenced to three years in jail and fined Rs.2000 under section 25 A of the Arms Act. If the fine was not paid, they would be kept in jail for another six months.

All the sentences would run concurrently.

According to the charge sheet, the trio had waylaid Rajib and his sister - when he was escorting her to home from the station - and tried to pour liquor on the girl and drag her away. When Rajib protested, they attacked him. He later succumbed to his injuries in the hospital.