Six nurses and a co-worker at a Chinese hospital have been knifed to death by another member of staff at a female employees' dormitory, state media said.
The man who carried out Thursday's attack in the resort town of Beidaihe in the northern province of Hebei told police he had "a history of mental illness", state news agency Xinhua said.
The suspect was named as Li Xiaolong by state broadcaster China Central Television (CCTV), adding he was about 27 and had been detained by police.
The attack was carried out early on Thursday "in the women's staff dormitory at the 281 Hospital in Beidaihe", it said in an online post, and another nurse had been wounded.
Chinese hospitals have seen a series of violent attacks, but they are more often carried out by angry patients against medical staff.
In April a 45-year-old man unhappy with his circumcision stabbed a doctor to death in the eastern province of Jiangsu. Three months earlier a man was sentenced to death for killing an ear, nose and throat specialist in neighbouring Zhejiang.
Meanwhile, a Chinese "quack" doctor who was released recently from prison after serving a term for a string of patients' deaths, has been jailed again over another fatal malpractice case.
Hu Wanlin, who theorises that water causes all diseases, dehydrated a young man to death after providing him with his treatment, a court found, sentencing him to 15 years in prison for illegally practising medicine, the Global Times newspaper reported on Thursday.
The official news agency Xinhua said that a court in Henan, central China, found that Yun Xunyang, a 22-year-old college student devotee of traditional Chinese medicine, died after taking a substance provided by Hu.
Hu, who had been blamed for at least 16 patients' deaths and claimed to be "omnipotent", believed that his patients needed to be dehydrated with a "magic medicine" using powerful salts, the paper added.
Hu found Xunyang's autopsy result hard to swallow, the Global Times said, claiming that he frequently consumes 1.5 kilograms of the salt and liquid mixture without ill-effects.
Hu, 65, began his self-described healing activities while serving a life sentence for killing a businessman, but was stopped in 1996 after 13 of his patients died, according to reports.
Nonetheless he was released, but was jailed again in 2000 for illegally practising medicine after three more patient deaths, including the then mayor of Luohe city in Henan.
On that occasion he was sentenced to 15 years, but he was again given his freedom early, the Global Times said.
China's government health insurance provides limited coverage to most rural residents, leading some to seek out cheaper alternative treatments.
It also has a long history of traditional medicine, much of it with no orthodox scientific evidence backing it up, and elements of which are blamed for driving illegal trade in endangered species.
Lu Wei, one of Hu's proteges who promoted Hu online as a medical master who could cure diabetes and AIDS, was also sentenced to 11 years in prison.