A severe type of acute hepatitis has been identified in almost 170 children across 11 countries in recent weeks, raising concerns from the World Health Organization (WHO) of the disease’s “unknown origin”.

Indonesian officials are investigating the mystery outbreak of liver disease in children, the health ministry said on Wednesday, after the first deaths were confirmed in the country. Indonesia’s health ministry said three children had died in hospitals last month in the capital, Jakarta, after displaying some of the symptoms.

As per medical professionals, prior to signs of liver inflammation, they have experienced nausea, vomiting, diarrhea, and abdominal pain.

The children, aged two, eight and 11, also had fever, jaundice, convulsions and loss of consciousness, said the ministry’s spokesperson Siti Nadia Tarmizi.

“At the moment, we suspect the cases as acute hepatitis, but we need to confirm that they are not due to known hepatitis viruses A, B, C, D, and Rb,” Tarmizi said.

She added that the health ministry was currently investigating the cause of the disease by running a full panel of virus tests.

The ministry also called on parents to immediately take their children to hospital if they showed any sign of the symptoms.

The emergence of a possible new disease afflicting only young children – most are under 10 years old with no underlying conditions – has caused concern in a global health community already grappling with Covid-19. The WHO also said that there was an “unexpected significant increase” in cases in the UK among young, previously healthy children, as well as in Ireland and the Netherlands.