A fire at a hospital in Beijing has killed at least 21 people and forced dozens of people to evacuate, Chinese state media have reported. As clouds of black smoke billowed into the sky late on Tuesday, people trapped in the multi-storey building apparently tied bedsheets into makeshift ropes and escaped by climbing out of windows, as seen in videos circulating on social media. Others took refuge by perching on air conditioning units on the exterior of the building. Emergency crews managed to extinguishd the fire, which broke out in the east wing of the inpatient department of Beijing Changfeng hospital, CGTN and other media reported, and at least 71 patients were rescued. The cause of the fire was under investigation. Most of the hospital building appeared to be without power late on Tuesday. The exterior of the building appeared blackened and charred in places. There was no official word by early Wednesday on how many of the dead were patients or the number of injured.