Additional District and Sessions Judge Muhammad Hasanuzzaman handed down the judgement on Tuesday.
The lifer are Shamim, 18, son of Chand Mollah of village Mohishvanga of Boraigrame upazila, Milton, 32, son of Abdur Rahim, Ashraful Islam, 22, son of Sirajul Islam of village Notabaria, Salim, 25, of Pabna Ishwardi area, Abdus Samad, 32, and Mofizul Islam, 32.
However, another accused Beauty Akhter got seven years jail.
Assistant Public Prosecutor (APP) Khondoker Abdul Hye said victim Anguri Abedin, 75, wife of late Joynal Abedin, went to see her crops land nearer to Bonpara-Hatikumrul high way on November 9, 2012, and went missing.
Later, on November 12, her dead body was recovered from a banana garden adjacent to her house.
The victim’s son Saiful Islam, a ward commissioner of Bonpara Pourashava, filed a case against 11 persons with Boraigrame Police Station the same day in this connection.