The process for rigging Supertech's illegal twin towers in Noida with explosives started Saturday, with the nearly 100-metre-all structures set to be demolished on August 28, officials said.

More than 3,500 kg of explosive will be filled in around 9,400 holes drilled in the columns and shears of the skeletal structures of the twin towers which will be razed to the ground.

The first batch of explosives reached the site in Noida's Sector 93A around 9 am amid tight police security, the officials said.

The charging process--rigging of skeletal structures with explosives--will take around 15 days, they said.

"The first batch of explosives was brought to Noida in a regulated quantity today from Palwal, Haryana. This was done after all requisite permissions and approvals were granted for the work by authorities concerned," an official privy to the demolition project said.

Meanwhile, additional police force has been deployed in the area around the twin towers, which have been made inaccessible to unauthorised persons, officials said.

A 500-metre road stretch in front of the towers has also been closed for normal traffic movement.

Supertech's Apex and Ceyane towers are scheduled for demolition in pursuance of a Supreme Court order last August which noted that the structures had come up in violation of building norms inside the Emerald Court society's premises.

Earlier, the scheduled demolition date was August 21. On Friday, the Supreme Court fixed August 28 as the date for razing the illegal twin towers and also relaxed the time frame till September 4 in case of delays arising from technical or weather conditions.