The family of a Briton who died when a Russian passenger plane crashed while trying to land have spoken of their sense of loss.
Mother-of-two Donna Bull was among the 50 people who died as the Boeing 727 was reportedly attempting a second landing at Kazan Airport in Tatarstan when it hit the ground and caught fire at around 7.20pm yesterday.
Ms Bull's widower Robert Crome answered the door at the family home in Cambridge today but was too distraught to talk after being told the news late last night.
He later issued a statement, saying it was a "very difficult and emotional time" for the family as they tried to come to terms with the shock and loss.
He said: "Donna was a wonderful mother to George and Kate, kind, thoughtful and caring to her family and her many friends.
"She was also a dedicated and hard-working professional, as a teacher and educationalist, so her students will all miss her greatly. Words are inadequate to express our grief and loss.
"We hope that the UK and Russian authorities can help to ease any administrative difficulties. We extend our heartfelt sympathies to all those families in Russia who too have lost their loved ones in this tragedy."
Foreign Secretary William Hague expressed his condolences, saying : "I was saddened to learn of the loss of life following yesterday's aeroplane crash. My thoughts are with the friends and family of those involved.
"We are providing consular assistance to the family of the British national whose death has now sadly been confirmed, and our British Embassy in Moscow will remain in close contact with the Russian authorities as they respond to this tragedy."
Ms Bull was "a very popular and well-respected member of staff" at Bellerbys College in Cambridge.
James Pitman, managing director for Study Group's higher education division - Bellerbys College and International Study Centres - confirmed Ms Bull's death and that of her Moscow-based colleague.
In a statement, he said: "We have received confirmation of the very sad news that our Bellerbys colleagues Donna Bull and Yana Baranova were on the plane that crashed in the Russian city of Kazan yesterday.
"Donna had flown out from the UK to Moscow earlier in the day, where she met Yana, and the two were heading to Kazan for the start of a 10-day marketing trip."
Mr Pitman said Ms Bull joined Bellerbys Cambridge in April last year as an A-levels programme manager.
"She was a very popular and well-respected member of staff and will be sorely missed by both her students and colleagues," he said.
Ms Baranova, although based in Moscow, forged close relationships with Bellerbys staff in the UK in her capacity as recruitment manager and will also be "sorely missed", Mr Pitman said.
"We offer our heartfelt condolences to both families during this very difficult time."
Bellerbys Cambridge was closed for teaching today, but open for staff and students to "come together and grieve".
All 44 passengers and six crew members were killed, the Russian government said.
Reports said the plane appeared to lose altitude as it was making its second landing attempt.
The Tatarstan Airlines plane had taken off from Moscow an hour earlier. There are no immediate indications of the cause.
Kazan, a city of about 1.1 million and the capital of the Tatarstan republic, is about 450 miles east of Moscow.
Alexander Poltinin, head of the local branch of Russia's investigative committee, said investigators were trying to determine why the crew were unable to land the first time.
Mr Poltinin said investigators are looking into possible pilot error or an equipment failure.
The traffic controller at Kazan airport who contacted the plane before the crash said the crew told him they were not ready for landing as it was approaching, but did not specify the problem.
The plane exploded on impact, and its burning fragments littered the tarmac.
Mr Poltinin said it could take weeks to identify some of the victims.
Investigators have found one of the plane's two black boxes.
The aircraft which crashed was built 23 years ago and had seen service with several carriers prior to being commissioned byTatarstan Airlines.
The company insisted that the plane was in good technical condition.
Russia has seen a string of deadly crashes in recent years. Some have been blamed on the use of ageing aircraft, but industry experts point to a number of other problems, including poor crew training, crumbling airports, lax government controls and widespread neglect of safety in the pursuit of profits.
The last fatal airliner crash was in December when a Russian-made Tupolev belonging to Red Wings airline careered off the runway at Moscow's Vnukovo airport, rolled across a snowy field and slammed into the slope of a nearby road, breaking into pieces and catching fire.
Investigators say equipment failure caused the crash, which killed five people.
A 2011 crash in Yaroslavl that killed 44 people, including a professional hockey team, was blamed on pilot error, and Russian investigators found that the pilots in two crashes that killed 10 and 47 people in recent years were intoxicated.
Diana Ischenko, marketing manager of Business Link in Kiev, Ukraine, said Ms Bull had delivered a presentation in the country in April.
She added: " It is unthinkable how such tragedies touch each one of us, our thoughts and prayers are with Donna's family at this difficult time."