The World Health Organization is investigating "another cluster of illness" in northern Congo, as a deadly mystery disease spreads in the region.

At least 60 people have died and over 1,000 more are sick from a deadly "unknown disease" spreading in a region of the Democratic Republic of Congo, the World Health Organization said. Local health officials in Congo are partnering with the World Health Organization to investigate.

The disease, which has infected more than 400 people and killed 53 within a few weeks, “poses a significant public health threat,” the World Health Organization said.