Canada tracked suspected Chinese spy balloon over Canadian airspace since last weekend: sources

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The suspected Chinese surveillance balloon that was found floating over sensitive military sites in the western United States had been tracked by Canada's government since last weekend as it passed through Canadians airspace, sources tell CTV News.

Canadian officials have not publicly stated whether the massive high-altitude balloon entered Canadian airspace. But sources told CTV News it had passed over the Canadian Arctic, Alberta and Saskatchewan before it was spotted over Montana on Thursday, as it flew over a nuclear launch site. Sources told CTV News it was tracked the entire time it was in Canadian airspace.

After being flagged by Norad, the joint U.S.-Canadian agency responsible for air defence in both nations, U.S. fighter jets investigated the balloon and determined it wasn't fitted with any weapons, but was equipped with high-resolutions cameras.

Even though Canadian officials had known about the balloon since the weekend, the Department of National Defence only confirmed it had been tracking the balloon late Thursday night, after the U.S. had announced the spotting of the balloon.

When asked about why the public was never informed about the balloon until after it had entered U.S. airspace, Public Safety Minister Marco Mendicino cited the sensitivity of the timing of the information.

"We have to strike that balance and make sure that we are not in any way compromising our operations and the techniques that we use to protect Canadians. But we're upfront about what we need to do and when we can share that information," he told CTV News Channel's Power Play on Friday.

"We do, and we work closely with our allies on that front as well. And we'll continue to do so that we can protect our perimeter, our sovereignty and our national security."

A statement from the Defence Department also mentioned it was monitoring a "potential second incident" but did not elaborate further. Sources told CTV News that a smaller object may have been released from the balloon that might pose a risk to planes. A flight advisory was issued to pilots in Alberta and Saskatchewan in response.

Sources also told CTV News U.S. intelligence knows of a total of at least four of these balloons from China sent to other countries, beyond the one currently over the U.S. That includes the one the Pentagon confirmed late Friday night floating over Latin America.

This incident comes at a time of heightened tensions between China and the West. In a statement, the Chinese foreign ministry said the balloon did come from China and apologized for its entry into U.S. airspace, but insisted the balloon was used for civilian research purposes rather than espionage.

U.S. Secretary of State Antony Blinken was set to visit Beijing on Friday for high-stakes talks, but the visit was abruptly cancelled. Global Affairs Canada (GAC) also announced it had summoned China's ambassador, Cong Peiwu.

"China's ambassador to Canada was summoned by officials at Global Affairs Canada," GAC spokeswoman Charlotte MacLeod said in a statement on Friday. "We will continue to vigorously express our position to Chinese officials through multiple channels."

With files from CTV National News Parliament Hill Correspondent Kevin Gallagher, The Associated Press and The Canadian Press.