Workers engaged for construction of a school building in the Secunderabad cantonment area stumbled upon an ammunition store believed to have been maintained by the British near Bollaram on Monday morning.

Authorities who took up excavation activity, found more than three tractor trolley loads of cannon balls. "We are not sure whether there is an explosive charge in the cannon balls. We are approaching the military authorities and ballistic experts", police said.

The cantonment was gifted by the defence authorities long time ago for setting up Trishul park Primary School next to Bollaram police station. Police are not sure how many cannon balls were still to be unearthed.