Stepping up her attack on DMK's first family on the 2G spectrum scam, AIADMK chief Jayalalithaa on Saturday demanded that chief minister M Karunanidhi, his daughter Kanimozhi, wife Rajathi and all others who had "maintained close contacts" with corporate lobbyist Niira Radia be interrogated by CBI to bring out the truth behind the scam.

"This has to be done immediately, for, the nation -- the people -- have a right to know the whole truth," Jayalalithaa said in a statement in Chennai.

The various conversations that Radia had with different members of the Karunanidhi family could not be dismissed lightly, she said, adding, they all knew that Radia was in a position to "deliver" what she took up.

"If the truth behind how the Prime Ministerial prerogative of appointing ministers was usurped by outsiders had to come out, Karunanidhi and his family members should be interrogated by the CBI," she said.