A passenger plane has crashed at an airport in the Russian city of Kazan, killing all 50 people on board.
一架客机在俄罗斯喀山市机场降落时坠毁，机上50人全部遇难。
The Boeing 737 had taken off from Moscow and was trying to land but exploded on impact at about 19:20 local time (15:20 GMT), officials said.
这架波音737飞机自莫斯科机场起飞，当其准备降落时由于受到冲击因而爆炸。事发时间为当地时间19:20（北京时间23:20）。
The Emergencies Ministry said there were 44 passengers and six crew members on the Tatarstan Airlines flight.
俄罗斯紧急情况部称，这架航班来自鞑靼斯坦航空公司，机上人员包括44名乘客和6名机组人员。
Investigators are now looking at whether a technical failure or crew error may have caused the crash.
事件原因尚在调查之中，起因或为机械故障或人员操作失误。
Investigative committee official Vladimir Markin told Rossiya 24 TV that experts were checking whether poor quality fuel and weather conditions could have been contributing factors. It was raining in Kazan when the aircraft crashed.
调查委员会官员弗拉基米尔·马尔金对俄国家新闻频道Rossiya-24记者称，专家正在就事件是否由于劣质燃油和恶劣的天气情况所致展开调查。该客机坠毁的时候喀山市正在下雨。
Among the dead was Irek Minnikhanov, a son of the president of the Russian Republic of Tatarstan, according to the official passenger list.
根据官方的客机乘客名单，伊列克·明尼哈诺夫——俄罗斯鞑靼斯坦共和国总统鲁斯塔姆·明尼哈诺夫的儿子也在遇难人员名单之列。
Aleksander Antonov, who headed Tatarstan's branch of the Federal Security Service, was also among the passengers.
俄罗斯联邦安全局鞑靼自治共和国分局首长亚历山大·安东诺夫当时也是机上乘客之一。
Russian President Vladimir Putin "expressed his condolences to the relatives of the victims in this horrible disaster", his spokesman Dmitry Peskov was quoted by the news agency Interfax as saying.
据国际文传电讯社报道，俄罗斯总统发言人佩斯科夫对媒体表示，俄总统普京对事故遇难者致以深切哀悼。
A government commission has been set up to investigate the cause, he said.
他表示，俄总统已责成政府紧急成立喀山空难事故调查委员会。
