OTTAWA - Canada's information watchdog has ordered a fresh probe into alleged political interference by a close aide to Conservative cabinet minister Christian Paradis.

The decision by Suzanne Legault means her office is now investigating four complaints about potentially illegal meddling by ministers' offices in the release of documents requested under the Access to Information Act.

Legault initiated the latest investigation after reviewing 1,200 pages of internal emails involving Sebastien Togneri.

Togneri has been under scrutiny since February for blocking the release of a document to The Canadian Press.

The latest batch of emails was turned over to Legault on Oct. 1 by officials at Public Works after the news agency reported that Togneri had meddled in at least three other information requests while he worked for Paradis at the department.

Togneri quit his post within hours of The Canadian Press report, sparking opposition calls for Paradis to do the same.

"Based on the documents that I received ... I felt I had reasonable grounds to start an investigation," Legault said Tuesday. "There are a lot of allegations."

Legault's office has been stretched thin coping with two formal probes into Togneri, and two other complaints of political interference at National Defence and Foreign Affairs.

Her investigators also continue a systemic inquiry begun this summer into broader allegations of political interference involving up to eight departments. Those claims emerged anecdotally from interviews her staff conducted with public servants who handle information requests.

Legault is personally overseeing complaints that began as a trickle and now threaten to overwhelm the limited resources of her office.

"These are investigations that I follow very closely," she said. "I've become more and more involved."

In July, Togneri ordered a Public Works official to "unrelease" a document already on its way to The Canadian Press, prompting the bureaucrat to sprint to the mailroom to pluck it from the pile of outgoing parcels. The 137-page document was a relatively innocuous report card on the government's handling of its real-estate portfolio.

Togneri was hauled before a House of Commons committee and acknowledged his mistake, calling the email "stupid" and testifying it was the only occasion when he had interfered.

But a batch of Public Works emails later obtained by the committee indicated otherwise, showing he had meddled in at least three more files, one involving asbestos exports, another about the visit to Ottawa of Barack Obama.

Under the law, ministers' aides can be tipped about the impending release of potentially embarrassing material but have no authority to censor information.

The act specifically forbids anyone to "direct, propose, counsel or cause any person" to conceal a record, with a maximum penalty of $10,000 or two years in jail. There has never been a conviction under the section.