Thousands of disgruntled students smashed up their high school campus in the southwestern Chinese province of Guizhou in the early hours of Friday morning after an outbreak of food poisoning made hundreds of them sick.



Students at Guizhou's Puding County No. 1 High School ran riot through their dormitories, smashing windows and prompting China's ruling Communist Party county leaders to rush to the school to deal with the incident, the county government said in a statement on its website.



It said no one was hurt, but made no mention of the mass food poisoning incident, prompting a slew of critical comments on social media sites.



Social media posts said 3,000 students at the high school's Hengshui campus near Guizhou's Anshun city had also staged large-scale protests after more than 400 students became ill.



"The local authorities sent in large numbers of police and have locked down the whole area," one tweet said. "But the police are just standing around and keeping watch; they didn't dare to intervene to stop the students."



During the protests, some of the students had smashed windows in the school canteen and in their dormitory buildings in protest at the poor food quality at the school, social media user @yuni said.



"Why were the students rioting? Because on Thursday night, the ambulances just kept coming to the campus all night," the user wrote. "The ambulances came from the People's Hospital, the Chinese Medicine Hospital and the Youhao Hospital."



"How must the parents feel when they get to the campus and see their kids at death's door?"



The tweet said protesting students were also angry over high fees and frequent use of out-of-date foods in the canteen.



"The dormitories are tofu buildings, and there are huge safety issues," @yuni wrote, suggesting they were poorly constructed and unstabe. "Why didn't the government talk about that, instead of just saying the students were rioting?"



"[Our leaders] should give the students an explanation."



Widespread sickness



A doctor who answered the phone at the Puding County People's Hospital said that "at least 10" students had been hospitalized there for food poisoning.



"I'm not sure exactly how many of them there are in our hospital, but it's more than 10," the doctor said.



"They're not doing too badly," he added. "Nobody is in critical condition, but some have been kept in for observation."



He said others had already been discharged.



"Some students went home after they were put on a drip," the doctor said.



He declined to give a cause for the food poisoning.



"We don't know that," the doctor said. "That is being investigated by the relevant departments."



An official who answered the phone at the Puding county government offices on Friday also declined to comment on the cause of the sickness.



"You should call the county propaganda department," the official said. But repeated calls to the propaganda department rang unanswered during office hours on Friday.



Safety issues



Chinese parents are reeling following a string of health and safety scandals to hit their children, including the deaths of more than 5,000 schoolchildren in "tofu buildings" made with substandard concrete during the devastating 2008 Sichuan earthquake, the sickening of thousands of infants with melamine-tainted milk formula, and a slew of lead-poisoning incidents surrounding smelting factories and battery makers across the country.



Last November, more than 3,000 students at a technical college in Guangdong rioted following a standoff with college management over poor food quality in the canteen.



Enraged by overpriced and poor food, as well as a rule banning the ordering of takeouts, students smashed windows in the controversial on-campus store and the canteen as well as computer equipment in college offices.



Beijing last year ordered a nationwide probe into safety at its kindergartens amid growing public outrage at the secret medication of pupils by some institutions and a slew of poisonings that left at least two children dead.



The two children, aged four and five, were reported dead, while 30 others fell ill after a mass poisoning incident in March 2014 involving a toxin used to control rats at a kindergarten in southwestern China.



Unlicensed educational establishments are a major problem in rural areas, where demand for child-care is huge among migrant work parents, who sometimes live in cities thousands of miles from their families.



Reported by Wei Ling for RFA's Cantonese Service. Translated and written in English by Luisetta Mudie.