A terrifying and explosive 'mud volcano' erupted. What's going on?

Social media videos showed people running into the streets as bright orange flames and smoke spewed into the sky.
Reuters

Two years on, Indonesia mud volcano still flowing

(Adds prayers, comments from rights body, environmentalist) By Heri Retnowati PORONG, Indonesia, May 29 (Reuters) - Two years after a mud volcano started erupting on Indonesia's Java island, thousands ...