PARIS -- Church bells tolled and officials laid wreaths across Europe on Armistice Day on Wednesday to pay tribute to the millions of soldiers killed during World War I.

Thousands of people lined the Champs Elysees boulevard in Paris to see President Francois Hollande lay a wreath at the Arc de Triomphe, where an eternal flame burns aside France's Tomb of the Unknown Soldier.

Smaller ceremonies were being held across France, where church bells toll to mark the hour when the armistice was signed Nov. 11, 1918 to mark the end of hostilities on the war's Western Front, and memorials list the names of each village's dead.

An estimated 10 million soldiers and other servicemen were killed in the 1914-1918 war, of whom 1.3 million were French. Millions, of many nationalities, lie buried across France's north and east along the war's Western Front.

In Britain, crowds paused to observe two minutes' silence at 11 a.m. in streets and town squares, offices, churches and railway stations. Hundreds stood quietly in London's Trafalgar Square and around the Cenotaph memorial in central London as the bongs of Parliament's Big Ben bell sounded the hour.

Among those marking the day -- which commemorates all those killed in war since the outbreak of World War I in 1914 -- were the widow and son of Fusilier Lee Rigby, who was murdered by al-Qaida-inspired attackers outside a London army barracks in 2013. They laid a wreath at St. George's Chapel, near where Rigby died.