More than 40 people, mostly women, who underwent cataract operations at a free camp in a government hospital in Periyakulam, Tamil Nadu, have lost their sight.

The patients, who complained of severe pain after the operation on January 24, were rushed to the Madurai Government Hospital in batches for treatment.

"The patients had complained of pain on the third day after the operation and when we opened the bandage we were shocked to see that the eyes were badly infected," a doctor at the hospital said.

"Restoring the sight is very difficult due to fungal infection in the eyes," he added.

The patients were from Andipatti, Periyakulam and other neighbouring places.

"Before the operation we had at least hazy vision, but now it is total darkness," two of the patients said.

Most of the patients said there was relief from pain, but they could not see anything.