Dozens of tourists in a Chinese water park near the China-North Korean border were injured after a wave machine for a “tsunami pool” malfunctioned on Monday.

Videos of the incident on Twitter and Chinese social media captured families and children being thrashed around at Yulong Shuiyun Water Amusement Park in Longjing, China. The footage has since gone viral.

The wave pool appears similar to ones in Canada which create artificial waves that periodically increase in intensity.

In a post on Chinese microblogging site Weibo, the Longjing Environmental Protection Bureau described how 44 people had been injured in the wave pool incident, with the majority of them being minor injuries.

“According to the initial stages of the investigation, the incident was caused by a power cut that damaged electronic equipment in the tsunami pool control room, which led to the waves in the tsunami pool becoming too big and injuring people,” the notice read translated from Mandarin.

The South China Morning Post reported that some of the injuries included fractured ribs, broken bones and other serious abrasions.

The Chinese outlet also reported that the park had been shut down pending the full outcome of the investigation.

The government’s social media post appeared to confirm what a theme park worker had told The Beijing Times on Tuesday in that a “problem with the equipment” had caused the incident.