OTTAWA -- Prime Minister Justin Trudeau is backing the decision by Canada's chief of the defence staff to relieve his second in command of his duties, but won't say anything more about the controversy swirling around Vice-Admiral Mark Norman.

Word emerged Monday that Norman was abruptly stripped of his responsibilities by his boss, Gen. Jonathan Vance, in a tersely worded letter dated Jan. 13.

Neither Vance nor Trudeau would say why Norman was relieved.

Norman, former commander of the Royal Canadian Navy, was appointed to the vice-chief position last summer.

The vice chief is essentially the No. 2 in the military hierarchy and is responsible for security, among other things.

Trudeau says the government is behind Vance, but like Defence Minister Harjit Sajjan, has nothing else to say.

"The chief of defence staff took a decision and this government supports Gen. Vance in the decision that he took," Trudeau told a news conference today in New Brunswick.

"I have nothing further to say on this at this time."

Citing an anonymous source, the Globe and Mail reported Monday that the decision followed an investigation into the alleged leak of "high-level secret documents."

Trudeau said Canada wants to reassure allies that security is observed.

"We continue to engage with our allies to demonstrate the seriousness with which we take issues of security, because it's essential for co-operation and collaboration," he said.

Conservative defence critic James Bezan said the government owes the public an explanation.

"This situation is unprecedented and it is odd that the government and the military are not providing any details," he said in a statement.

"Of course we expect all necessary precautions to be taken when there are national security and privacy implications involved. However, when a decision of this magnitude is made Canadians deserve to be kept informed."

The RCMP would not say whether they had Norman under investigation for any reason, noting they generally never confirm or deny who is or isn't under scrutiny.

But the military police said they were not involved.

"We weren't, and we are not, investigating on this case," Maj. Jean-Marc Mercier, a public affairs officer with the military police group said in an interview.

Vice-Admiral Ron Lloyd -- who took over command of the navy from Norman -- has been appointed as interim vice chief.