A test blast was carried out at one of the twin towers of Supertech here on Sunday, officials said.

The Supreme Court had on August 31 last year ordered demolition of the twin towers which had come up in violation of building laws.

A siren lasting a few seconds went off at 2.15 PM followed by two to three sirens at 2.30 PM, moments preceding the test blast.

According to officials, the test blast was carried out with five kg explosives in the Apex tower.

The test blast was held to ascertain the amount of explosive which would be needed during actual demolition of both the towers on May 22.