CAIRO, Oct. 31 (Aswat Masriya) - All 224 passengers and flight crew members on the Russian civilian flight that crashed in the Sinai Peninsula on Saturday morning have "unfortunately" died, the Russian Embassy in Egypt said on its Facebook page. 

Egypt has not officially made any announcements on the casualties. 

The Russian plane, an Airbus A321 took off from South Sinai's Sharm El-Sheikh resort city with 217 passengers and seven crew members on board at 5:51 am.

The flight was operated by Kogalymavia, which is privately owned, and officially changed its name to MetroJet several years ago. Airbus said on its website that the plane that crashed was produced in 1997 and has been operated by Metrojet since 2012. 

Within minutes, air traffic controllers lost contact with the plane and it disappeared from radar after 23 minutes from take-off. The wreckage was found south of North Sinai's al-Arish city.  

The Egyptian civil aviation ministry said the plane was at an altitude of 31,000 feet when it disappeared.

Russia has declared a state of mourning on November 1. National flags will be lowered across the country and entertainment shows will be cancelled. 

The cause of the crash remains unclear and Egyptian Civil Aviation Minister Hossam Kamal said it is "premature" to decided on the cause of the crash, which is currently being  investigated.

Russian President Vladimir Putin instructed Prime Minister Dimitry Medvedev "to form a state commission to investigate" the crash. 

Russian authorities have the right to participate in the investigation, a source at the Egyptian aviation ministry source earlier said. 

A team from the air crash investigation department at the ministry of civil aviation went to the site of the crash to inspect it and recover the black boxes, the source said.