Premier Kathleen Wynne has filed a libel notice against Opposition Leader Tim Hudak.

It's over accusations she was behind an alleged plan to wipe computer hard drives in the premier's office to hide documents related to the cancellation of two gas plants.

A spokeswoman for Wynne says libel notices have also been served to the Ontario Progressive Conservative party and Tory MPP Lisa MacLeod, who responded on Twitter by tweeting "Oh dear."

Earlier this week, Wynne warned the Tories to stop accusing her of masterminding a plan to wipe the computer hard drives in the premier's office.

Wynne said Tuesday that her lawyer had sent Hudak a cease and desist order.

The Tories said it's clear the plan to wipe hard drives in the premier's office happened while Wynne was premier-designate of Ontario.

Wynne acknowledges an outside computer expert who was brought in and given unprecedented access to government computers had separate contracts with the Liberal party and Liberal caucus.

Ontario Provincial Police have alleged in court documents that the computer access was given by David Livingston, McGuinty's former chief of staff.

But Wynne says no members of McGuinty's staff had access to the premier's office after she took over.

Police say computer experts cannot determine when 20 of 24 hard drives were accessed with a special password that was valid for weeks after Wynne was sworn in.