None could be arrested in this respect.

Sources said two students of the primary school Raihan, 7, and Rustam, 6, found outside their school two black tape wrapped cans which were left by some unidentified people.

Raihan and Rustam took the cans behind the school and tried to unwrap them when a landlady of a house next to the school started screaming "bomb","bomb" after she saw them unwrapping the cans.

The two boys threw the cans out of fear to the pond.

Being informed, Benapole police recovered the bomb from the pond after a two-hour search.

Different intelligence agencies are investigating the type of the bomb and enquiring whether there was any terrorist intention behind the leaving of the bomb outside the school.

A case was filed in this connection.