A charred wheelchair is discovered among the debris of a nursing home as firemen clear the scene in Lushan, Henan Province on Tuesday. A fire on Monday evening killed 38. Photo: CFP

Thirty-eight people were killed and six injured in an inferno at a nursing home in Henan Province Monday night, the latest accident at China's nursing homes which has drawn concerns over the supervision of facilities for the country's growing aging population.

Authorities have arrested 12 people suspected of being responsible for the tragedy, including seven nurses and five staff members, according to a statement issued by the local government on Tuesday.

Fire broke out at a row of bungalows at the privately-owned Kangleyuan Rest Home in Lushan county. The razed areas included the beds of 51 senior citizens, 44 of whom were in the building when the fire started at 7:33 pm on Monday. Many of them were too sick or weak to move.

Two people were seriously injured while four others suffered minor injuries.

The fire was put out an hour later. The cause of the fire is under investigation.

The tragedy shocked the nation. President Xi Jinping demanded that those responsible be punished for the incident under the law after a thorough investigation.

The accident brought to light long-standing problems with China's nursing homes.

Observers warned that the world's most populous country would face more challenges on coping with the aging population if the government fails to establish a system to guide and supervise the nursing institution market.

About 15 percent of China's population was at least 60 years old as of 2014, higher than the UN's standard of 10 percent for an "aging society." The group is likely to reach 30 percent by 2050.

It has become increasingly difficult for senior citizens to find a decent nursing home across the country as the construction of such facilities lags behind their growing numbers. Many have to wait for years or cope with sub-standard nursing homes.

In the past two years, media have reported at least 10 accidents at rest homes, which included building collapses, fire accidents and missing seniors, resulting in the death of 20 seniors.

On New Year's Day this year, two senior citizens died in a fire at a nursing home in Nanyang, Henan Province.

Survivors of the Lushan fire said that the burned bungalows were built with steel sheets stuffed with flammable materials, and the nursing home lacked nighttime staff, according to Xinhua.

Local governments have failed to come up with standards for construction materials for nursing homes, said Peng Xizhe, dean of the School of Social Development and Public Policy at Fudan University.

Yao Yuan, a professor of the School of Sociology and Population Studies at the Renmin University of China, told the Global Times that local fire departments should expand their drills to social welfare institutions, including nursing homes and orphanages.

A 2015 bluebook on Beijing's nursing home industry shows that the number of senior citizens in the city will increase by  1 million by 2020, but 80 percent of its nursing homes are occupied, Beijing-based The Mirror reported Tuesday.

An employee from a nursing home in Beijing's Chaoyang district said that more than 500 senior citizens have applied for their 100 beds as of Tuesday.

"There's an urgent need to deal with the aging problem, as a great number of senior citizens who only have one child will live in nursing institutions soon due to China's family planning policy, which will pose greater challenges and pressure to the country's welfare system," Peng told the Global Times.

China had 32,000 registered homes and 220,000 caregivers as of March, but the number of people older than 60 has exceeded 200 million.

Pei Xiaomei, a sociologist at Tsinghua University, said that the government should invest in training more professional nurses at medical institutions rather than simply allocating funds to nursing homes, which have been made to appear as part of the local governments' achievement, according to China News Service.

Xinhua contributed to this story