Police in Beijing are investigating claims of abuse at a kindergarten operated by Chinese pre-school operator RYB Education Inc, the second high-profile case of alleged child abuse at a Chinese nursery in the last month.

The official Xinhua news agency said late on Thursday that police were investigating allegations some teachers had abused infants at the school after parents raised concerns to police after finding unexplained needle marks on their children’s skin.

In a statement posted on its official micro blog on Friday morning, RYB said it was taking the case seriously, apologised to parents and said it was helping authorities.

“We are currently working with the police to provide relevant surveillance materials and equipment; the teachers in question have been suspended and we are cooperating with the police investigation,” it said.

The case and a similar one this month involving a nursery in Shanghai linked to online travel agent Ctrip.com has sparked anger and concern in China about hidden abuses, poor oversight and the lack of qualified teaching staff.

In a commentary, Xinhua said there were “hidden dangers” due to staffing issues and rules not being enforced. “Why weren’t these abuses detected earlier and stopped in time?” it wrote.

A news report on China Central Television (CCTV) on Friday morning showed video of police and angry parents outside the school in Beijing’s Chaoyang district looking for answers.

RYB, which listed in New York in September, says on its website it operates a network of over 1,300 directly owned and franchised play-and-learn centres and nearly 500 kindergartens in around 300 cities and towns around China.

The investigation comes after videos emerged earlier this month of teachers at a kindergarten in Shanghai physically abusing and force-feeding infants.

Chinese education providers have been attracting major investment, while others have been looking for global listings, latching onto fast-rising demand from Chinese parents for high-end education services for their kids.