Noida, Jul 25 (IANS): Two youths died while two others were left in a critical condition after they entered a sewer tank in Sector 6, Noida, to retrieve a cricket ball on Sunday morning.

The tragedy occurred after a cricket ball fell into a Jal Board sewer plant tank. To retrieve the ball, four youths went inside the tank, but soon fell unconscious, the police said.

Though the youths were warned by a Jal Board official present on the spot from entering the sewer tank, they did not pay heed to him. Soon after entering the tank, the youths fell unconscious after coming in contact with the toxic gas inside the sewer tank.

As the four youths fainted inside the tank, a rickshaw-puller and the tank operator standing nearby raised an alarm.

After some time, with the help of local people, all the four youths were taken to the hospital, where two were declared dead by the doctors, while the other two were shifted to Delhi's Safdarjung Hospital in a critical condition.