Time, one of M F Husain's paintings worth Rs seven million, has been lost in Hyderabad.
The painting is believed to have gone missing some time between January 6 and 7.
Husain regretted that the organisers did not inform him about the loss.
Another highly-valued painting, that of Hyderabad-based Alex Mathew, which was also exhibited at the event at the Nizam College Grounds in Hyderabad, was also lost.
"I had lent my painting for a social cause, but the organisers have been thoroughly irresponsible. Such was their audacity that they did not even inform me about the loss of my painting," a visibly distressed Husain said.
The Asian Social Forum meeting had attracted about 12,000 delegates from all over India and several Asian countries. The 4 ft x 13 ft painting was put up for display on the third day of the six-day event, in Husain's presence.
"I am feeling sad not because of the monetary loss, but the painting was dear to me like a baby. If somebody had asked me, I would have given it to him as a baby is given for adoption," he said.
Husain said the organisers were supposed to return the painting on January eight.
However, when it was not returned, Husain on Sunday evening got in touch with the organisers of the ASF meeting, who informed him about the loss.
In fact, it was only on Monday that they lodged a formal complaint at the Abids police station.
The organisers, including prominent criminal lawyer and People's Union for Civil Liberties (PUCL) president K G Kannabiran, have now written to Husain informing him about the loss of the painting and expressing their regrets.
The painting is part of a series Husain is doing on eminent poets of India. "My work on the revolutionary poet Makhdoom Mohiuddin would be ready by June 20," he said.