More effort is needed to improve training for mental health caregivers for the elderly, as well as those based in the community, experts and industry insiders said.

Guo Ping, a researcher at the China Research Center on Aging, said many extreme events resulting in injury and death, including suicide, have occurred in nursing homes in recent years.

"They mainly happen because of management loopholes at institutions and poor nursing services, such as a lack of timely mental health care," he said.

Some elderly people act irrationally and emotionally partly because of normal brain decline. When they are in otherwise good health, their behavior can be dangerous, Guo said.

He warned that conflicts easily occur among such people if caregivers fail to notice problems early.

Only about 4 to 5 percent of caregivers in Chinese nursing homes have accredited professional training, including physical and mental health care, Guo estimated, without providing specific figures.

His comments came after two deadly arson attacks on Friday.

Eleven elderly people were killed after a man set fire to a nursing home in Hailun, Heilongjiang province.

Wang Gui, a 45-year-old resident of the home who also died in the blaze, started the fire after he suspected another resident had stolen 200 yuan ($30) from him.

A lack of timely psychological counseling for Wang when he had a conflict with a neighbor as well as loopholes in safety management were the main reasons for the disaster, investigators said on Saturday.

The compensation for each victim's family will be between 88,800 and 355,200 yuan, based on their age, investigators said.

In Wenzhou, Zhejiang province, arson at a recreation center for the elderly on Friday killed two people and left 12 injured.

The center, a two-story house known to locals as the Pavilion for the Elderly, was where elderly residents gathered to play cards and mahjong after dinner. An estimated 20 to 30 people went there at night every day, residents told Qianjiang Evening News.

According to a statement from city police, the fire was started by a 55-year-old man surnamed Lin, who had been in a dispute with someone at the center over the time the air conditioner should be turned off, four days before the fire.

Lin rushed into the house with a lighter and a bottle of petrol and set the fire at 8:30 pm, the statement said, adding that Lin has been detained for questioning.

Among the dead was a 91-year-old woman named Chen who was in a room on the second floor and could not escape. The other fatality, a 60-year-old woman, died after being taken to a hospital.

"The elderly are just like babies, very grumpy and emotional," said a care worker in Wenzhou who gave her name as Li.

A native of Hubei province, she was a babysitter for about five years before she began looking after the elderly in 2008, because the latter are "less noisy".

"They ask for very little material stuff, but crave a lot of company and attention," she said.

Li cares for an 89-year-old woman, whom she said she cannot leave alone for more than two hours. She usually runs daily errands while the woman is napping and only returns to her hometown to visit family for less than three days a year during Spring Festival.

Lin Xiaoling, 23, works at a private nursing home in Tianjin. She said on Sunday that her institution has asked its employees to be vigilant during their daily work after the two arson attacks.

"All kinds of dangerous tools, such as fruit knives, cigarette lighters and ropes, are now kept by workers and only provided to the elderly when they are needed," she said.

Lin said she gave special attention and care when she noticed patients were in a bad mood. She has been working since July 2012 when she graduated with a bachelor's degree in nursing for the aged.

Researcher Guo urged authorities to improve community care for the elderly.

"When more healthy elderly people can receive better care from their families and communities, some such incidents of violence can be avoided," he said.