Bengaluru, May 13 -- The recovery of gelatine sticks, batteries, wires and a crude circuit-like assembly near a route used by Prime Minister Narendra Modi during his recent Bengaluru visit has led investigators to examine whether the materials were intended to trigger a larger security scare, according to police officials involved in the probe.

What initially appeared to be a case involving quarry explosives has now evolved into a multi-agency investigation after electronic components were recovered from a cardboard box found during security sanitisation operations near the Bengaluru-Kanakapura highway.

Senior investigators said the materials recovered from the site raised concern because the combination of explosive substances and circ...