LONDON (AP) — Representatives of five nations that lost citizens when Iran shot down a Ukrainian airliner last week met Thursday in London to press Tehran to conduct a full and open investigation into the tragedy.

The foreign ministers of Canada, the U.K., Afghanistan, Sweden and Ukraine lit candles at a vigil in memory of the dead passengers and crew members before the meeting at the Canadian High Commission on Trafalgar Square.

All 176 people aboard the Ukraine International Airlines died when it was brought down by ballistic missiles shortly after taking off from Tehran’s Imam Khomeini International Airport on Jan. 8.

The victims included 57 Canadian citizens, as well as Ukrainians, Swedes, Afghans, Britons and Iranians.

Iran initially blamed a technical fault before acknowledging in the face of mounting evidence that its paramilitary Revolutionary Guard had accidentally brought down the jetliner.

British Prime Minister Boris Johnson has called for a "comprehensive, transparent and independent international investigation" of the crash.

Canada — which doesn't have an embassy in Iran — has demanded official status in the investigation. Canadian Transport Minister Marc Garneau said Wednesday that two Canadian investigators were in Iran as part of an international team and had good co-operation, but Garneau wants their participation in the probe formalized.

Garneau said the plane's voice and flight data recorders are in Iranian hands, but another two Canadian investigators are ready to go wherever and whenever they are examined.

The downing of the plane came amid heightened tensions between Iran and the United States over the killing of Revolutionary Guard commander Gen. Qassem Soleimani in a U.S. drone strike. Iran fired missiles at Iraqi bases housing U.S. troops in retaliation for his death.

American allies have avoided blaming the Trump administration, but Canadian Prime Minister Justin Trudeau said the crash victims would be alive today if tensions had not escalated in the region.

"If there was no escalation recently in the region, those Canadians would be right now home with their families. This is something that happens when you have conflict and the war. Innocents bear the brunt of it," Trudeau told Global News Television this week.