The action came on a complaint from the AIADMK IT Wing in this regard.
The communication from Tamil Nadu Chief Electoral Officer Rajesh Lakhoni to Karunanidhi said telecast/broadcast of all political advertisement in all electronic form should be "stopped 48 hours before the day of close of poll."
The AIADMK had complained that DMK was "doing campaigning in social media in favour of" Karunanidhi and that it was promoting its manifestos among voters.
Citing EC guidelines, Lakhoni said during this 48-hour window, no person shall, among others, convene or address public meetings or processions or propagate any election matter.
"I am therefore to direct you to stop posting/displaying of such political propaganda/campaign in the social media immediately on receipt of this letter and to offer your explanation as to why action should not be taken against you for violating the code of conduct of Election Commission of India on or before 5 PM on May 17, 2016," he said.
'Aspire' K Swaminathan of the AIADMK IT Wing, which had filed the complaint with the EC said "this is not the first time DMK is going beyond EC rules."
"This time, they have taken it to the social media," he said.
The Election Commission had on Saturday night issued show cause notices to AIADMK supremo and Tamil Nadu Chief Minister Jayalalithaa and Karunanidhi for violating model code, saying their election manifestos do not "substantially" fulfil its guidelines.
Last Updated 6:36 PM IST