New Delhi, Aug 25 - Following the protest move of the other Indian Institutes of Technology (IIT), over 400 professors of IIT-Delhi went on casual leave Tuesday over pay disparities.

'All the 428 professors have gone on leave for one day. The ministry of human resources development is the real villain,' said Hem Chandra Gupta, professor of Physics at IIT-Delhi.

While IIT-Madras and IIT-Kharagpur professors had gone on leave Friday, those from IIT-Bombay and IIT-Roorkee boycotted classes Monday to highlight the 'government's apathy' towards their pay related problems.

The professors alleged that the HRD ministry had sidelined the Goverdhan Mehta Committee report which had recommended better pay structure for IIT professors.

'The HRD ministry has tinkered with the report here and there. I don't know what benefit they will get by not paying the IITs well,' Gupta added.

He said that IITs are the only global brand and not taking care of the institutes would prove a disaster.