By Colleen Howe BEIJING, May 26 (Reuters) - After prices for Chinese coking coal soared to two-week highs following the country's worst mining tragedy in more than a decade, analysts expect the incident will put pressure on coal supplies during the summer when demand usually spikes.

Chinese authorities are investigating the coal mine explosion in Shanxi province, which exposed alleged violations and rescue failures.

Over 120 people were undergoing hospital treatment, with local news agencies reporting hundreds of personnel dispatched.

State broadcaster CCTV News released footage on Monday capturing the moment of a gas explosion at Liushenyu coal mine in Qinyuan county of Changzhi, North China's Shanxi Province — a harrowing lesson that has sounded an alarm for coal mine safety across China,