Up to 20,000 people, among them Prime Minister Lars Lokke Rasmussen, gathered for a candlelight vigil at the gates of the French embassy in Copenhagen mourn the victims of the Paris attacks.
The flight had been bringing holidaymakers back to Saint Petersburg, Russia's second largest city, when it disappeared off radar screens while over the Sinai peninsula.
Shell-shocked Hollywood mourned James Horner, the Oscar-winning composer of musical scores for "Titanic" and "Avatar," who died in a plane crash aged 61.
Relatives of 116 people killed in an Air Algerie crash in July visited the scene of the disaster in remote hazardous northern Mali under tight military guard.
Grieving relatives joined political and religious leaders at a sombre German memorial service for the victims of last month's Germanwings crash in the French Alps.
Germany will hold a national memorial ceremony and service for victims of a Germanwings flight that crashed in the French Alps, killing all 150 aboard, on April 17.