New Delhi: Four children were crushed to death in south Delhi Sunday when the parapet of an under-construction building collapsed, police said, adding two people, including the builder, have been arrested.

The victims - Divya (9), Monu (10), Nitin (10) and Gaurav (12) - were taken to Safdarjung Hospital where doctors pronounced them dead. The incident took place at 12.15 p.m. at block-D in Suman Colony of south Delhi's Chhatarpur Extension area.

The children were playing carrom in an open field just behind the under construction building when the incident occurred. The construction work was on at the fifth floor of the building. According to a Municipal Corporation of Delhi official, the construction was illegal and was to be soon demolished by the civic agency.

"A case regarding the incident has been registered and two people -- builder Sandeep Saini and labour contractor Sahil -- have been arrested. A case of negligence has also been registered against owner Baldev Singh," said a senior police officer.

Baldev Singh, who is out of city, has been informed about the incident and asked to return as soon as possible, the officer added.