Four siblings, aged between five and 14 and left unattended by their parents for months, apparently committed suicide by drinking pesticide in southwest China, the government and state media said Friday.

The children, a boy and his younger sisters, were found by a villager while struggling with convulsions after taking the poison late Tuesday at their home in Bijie in the remote province of Guizhou, the official Xinhua news agency said.

They died soon after and police believe it was a suicide, in a case highlighting the plight faced by rural children left behind by their migrant guardians.

Their mother left in February 2013 after being beaten up by their father, the provincial civil affairs authorities said in a statement. Xinhua said her whereabouts are unknown.

The father, identified as Zhang Fangqi, left the town to work elsewhere in March 2015, wiring money back periodically, Xinhua added, citing the Communist Party chief of the village and a family relative.

The incident sparked widespread public sympathy and prompted Chinese Premier Li Keqiang on Friday to call for "an end to such tragedies", vowing to punish officials who are lax in providing due assistance to families with similar problems.

A local government website said an investigation had been launched and that several officials had already been suspended or removed from their positions.

The children had apparently suffered severe domestic violence in previous years and the boy had attempted to commit suicide before, Xinhua said in a Chinese-language report late Thursday, citing the same female relative.

At one point the child's left arm was broken and his right ear was torn by his father, she said.

In August 2012, the boy ran away from home for more than 10 days and was later made by his mother to stand in the sun naked for over two hours as punishment, she added.

Offspring of China's vast army of migrant workers, referred to as "left behind children", often stay in their rural homes, usually with their ageing grandparents, partly because access to kindergartens and schools in cities is either extremely hard to obtain or expensive.

The country has more than 60 million "left behind children" and nearly 3.4 percent of them live by themselves, Xinhua said, quoting a 2013 report by the All-China Women's Federation.

Incidents involving such children often make headlines in China, including one in Bijie in November 2012, when five boys aged about 10 were found dead in a dumpster after they climbed inside to escape the night-time cold.

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