Xi Jinping urges authorities to ‘spare no effort’ in rescue operation after explosion in northern Shanxi provinceAt least 90 people have been killed in a gas explosion at a coalmine in northern China’s Shanxi province, in the country’s worst mining disaster in 17 years.The explosion happened on Friday at 7.29pm (12.29 BST) while 247 workers were underground at the Liushenyu coalmine in Qinyuan county, the state media