SAINT PETERSBURG: Flags flew at half-mast in Russia on Sunday as the country mourned its biggest ever air disaster after a passenger jet full of Russian tourists crashed in Egypt’s Sinai, killing all 224 people on board.

The flight was bringing holidaymakers back to Russia’s second largest city Saint Petersburg when it went down in Egypt’s Sinai, with international experts now at the scene trying to discover the cause of the tragedy.

“Can you imagine, people came (here) to pick up their children, grandchildren, only to find out that they no longer exist,” said Galina Grigoryeva, 34, one of many people who brought flowers to a makeshift memorial near the arrivals area at Saint Petersburg’s Pulkovo airport.

“When I found out about this, I just cried,” she told AFP, her five-year-old in tow with a cuddly toy for the memorial to honour the children who died, some as young as 10 months.

Flags were at half mast on the parliament building, in the Kremlin, and on other official buildings in honour of the victims, most of whom were from Saint Petersburg and its surrounding region.

Authorities set up a crisis centre at a hotel near the airport where relatives of the victims were invited to provide DNA samples and psychologists were on call.

Russia’s state-owned rolling news channel Rossiya 24 periodically interrupted coverage with moments of silence and flashed photos of smiling crash victims apparently taken on their holiday and posted on social networks.

Some people had been on their first foreign holiday, some had never flown before, and one couple was on their honeymoon, the channel said.

“Many of us could have been on this plane, and this tragedy cannot leave any of us indifferent,” Patriarch Kirill of the Russian Orthodox Church said as he led one of religious services held Sunday in the victims’ memory.