New Delhi, Jan 10 (Agencies): Four children were injured in south-east Delhi on Monday morning when a drum containing chemicals exploded outside a printing press while they were burning waste material to beat the bone-chilling cold.

The incident took place outside the press located in Okhla Phase-II at around 9 am and two fire tenders were rushed to the spot, fire brigade officials said.

The children were burning waste material to beat the chill near the drum containing highly-inflammable chemical when the incident took place.

"The drum got heated up and exploded. Four children suffered injuries and were rushed to Safdurjung Hospital," the officials said.

It has been a cold morning as icy winds were blowing across the city at a speed of nine km per hour while the mercury fell to a minimum of 4.7 degree Celsius.