The woman, who has been identified as Somitra Devi, had gone missing since Saturday, although it was not reported by the family, according to the police.
Somitra's son Bablu informed the police today around 4 pm that his mother's body was found inside the bed box, a senior police officer said, adding that there were strangulation marks on her neck.
Somitra's another son is missing since morning.
Police suspect it to be a murder and has registered a case in this regard, he said, adding that the body has been sent for post mortem.
"The son Bablu claims the family could find neither his mother nor his brother in the house today morning. A foul smell was emanating from the bed following which they opened the bed box and found the woman's body," the senior officer said.
"The victim's son is the primary suspect as he has been missing since morning. But we are also looking at the possibility of the involvement of other family members and probing the case from all angles," he said.