Two cousins drowned in a pond at Pakhiura area of Rajibpur Upazila of Kurigram district on Monday afternoon.
The deceased were identified as Hossain, 3, son of Nurnabi and Kamrul Hasan, 2, son of Abdul Alim of the upazila.
According to locals, two children fell into the water body in the absence of family members when they were playing on the bank of the pond near their house this afternoon.
At one stage of a frantic search that followed the discovery that they were missing, the bodies of the children were found floating in the pond.
Selimur Rahman Selim, officer-in-charge (OC) of Rajibpur Police Station, said they went to the spot immediately after getting information.
A separate unnatural death (UD) case will be filed in this regard, he added.