Dozens of passengers were hospitalised after their plane crashed just minutes after take-off in Kazakhstan on Friday.

At least 12 people were killed, Kazakh officials said.

The Bek Air aircraft lost altitude after leaving Almaty airport — en route to the capital Nur-Sultan —, hit a concrete fence and a two-storey building around 2.22 am CET.

An investigation is underway but Kazakhstan's Deputy Prime Minister, Roman Sklyar, said there were two skid marks from the tail end of the plane on the runway, indicating it struggled to take-off.

Those that died were mainly at the front of the aircraft, he added.

One survivor said the plane started shaking less than two minutes after takeoff.

"At first, the left wing jolted really hard, then the right. The plane continued to gain altitude, shaking quite severely, and then went down,'' Aslan Nazaraliyev, one of the passengers who survived the crash, told The Associated Press

There were 98 people on board and at least 54 were hospitalised, around 10 of them in a critical condition, officials said.

Russian media reported the injuries included cerebral, hip, and lower limb injuries.

According to Flightradar24, the plane was a Fokker 100.

Emergency Situations Ministry of the Republic of Kazakhstan photo via AP

Later on Friday, people were pictured leaving flowers at the airport to pay tribute to victims of the crash.

Saturday (28 December) has been declared as a national day of mourning in Kazakhstan.

What do we know about Bek Air?

Bek Air was founded in 1999 with the aim of providing VIP flights to the business community.

Today, the firm says it has become the first low-cost airline to serve a wide range of domestic destinations across the country.

Bek Air bought its first Fokker 100 in 2012 and says it now has a fleet of seven such aeroplanes.

On 27 March 2016, a Bek Air-operated Fokker 100 got into trouble approaching Astana International Airport, according toaviation-safety.net. Its landing gear failed to deploy but there were no injuries reported.

Reaction to the crash

Kazakhstan's President, Kassym-Jomart Tokayev: "Let me express my deepest condolences to the friends and families who lost their dear loved ones in the tragedy occurred on December 27. All those injured will be rendered assistance. The Government commission led by Askar Mamin was set up. All those responsible will carry severe punishment in accordance with the law."

Kazakhstan's Deputy Prime Minister, Roman Sklyar: "Today, we found two consecutive sets of skid marks from the tail end of the plane on the runway at intervals 300-400 metres, meaning the aircraft touched the runway twice while taking off. Mostly passengers who were in the front part of the aircraft died. Flight recorders have been found and have been brought for inspection."

Bek Air, the firm operating the aeroplane, said: "On behalf of Bek Air, we express our deepest condolences to the families and friends of the passengers injured in the crash of Flight 2100. For its part, the airline is doing everything possible to clarify the details of the incident as soon as possible. We sincerely grieve with everyone and share the bitterness of irreparable loss." (Agency report)