In Pictures: US servicemen honoured at start of Memorial Day weekend

US Army soldiers placed small US flags at more than 230,000 headstones in Arlington National Cemetery in Arlington, Virginia on Thursday. Known as Flags In, this tradition has been carried out annually since 1948. It also marks the start of the Memorial Day weekend activities. Memorial Day is observed on the last Monday each May and honours the men and women who have lost their lives while serving in the US military. This year, Memorial Day falls on May 30, 2016.