Harbhajan also faces separate action from the BCCI, which has asked him to explain, "as a contracted player", his role in the incident which came to light after Sreesanth was reduced to tears in front of the cameras.
The BCCI said on Monday that Sudhir Nanavati, a lawyer, has been appointed to conduct a "preliminary inquiry" and submit a report "within 15 days" to Sharad Pawar, the BCCI president, who will refer the findings to the board's disciplinary committee for possible action.
Harbhajan has been fined 100 per cent of his match fee for Friday's game. Lalchand Rajput, the coach of the Mumbai side, has also been found guilty of a level 2 offence and fined 15 per cent of his match fee.
"Rajput was right behind Harbhajan when the incident took place. He didn't take any step to restrain him. He has been fined 15 per cent of his match fee," said Lalit Modi, the commissioner of the IPL who is also a vice-president of the BCCI.
Earlier, the Mumbai Indians stand-in captain was temporarily suspended from the DLF Indian Premier League and missed the Mumbai Indians match on Sunday.
The off-spinner was charged with the violation of a level 4 offence of the ICC player code of conduct.
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