A fire at a care home in central China has killed 38 people and injured six, according to state media.

The official Xinhua News Agency said the blaze swept through an apartment building being used as a privately run rest home in the city of Pingdingshan in Henan province.

Xinhua said two of the injured were in serious condition, and a rescue operation was still under way. The cause of the fire was unclear.

With a rapidly ageing population and under-resourced social security net, China faces increasing pressure to provide safe and affordable care for the elderly.

In 2013, a disgruntled resident set fire to a rest home, killing himself and 10 others, in the north-eastern province of Heilongjiang.

Xinhua said the building housed 51 elderly people and quoted one survivor, 82-year-old Zhao Yulan, as saying only two of the 11 people living in her room made it out alive. Some of the remains of people killed in the fire were burned beyond recognition, Xinhua said.

President Xi Jinping urged rescue personnel to urgently aid the injured and victims' families and determine the cause of the fire as well as who was responsible, state broadcaster CCTV said.