The Democratic Republic of the Congo's Ebola outbreak has spread to a fourth province after suspected cases were detected in Tshopo, raising fresh concerns as the death toll climbed to 600, health authorities said Wednesday.

The outbreak has infected 1,759 people across Ituri, North Kivu and South Kivu since it was declared on May 15, according to the latest government situation report.

Health officials said two suspected Ebola cases were identified in Kisangani, the capital of Tshopo province. One case has been linked to the outbreak's epicenter in Niania health zone in Ituri, while the second has no confirmed epidemiological link beyond Kisangani. Both cases are undergoing confirmatory testing before being added to the official tally.

Authorities have already stepped up surveillance, contact tracing and other containment measures in Kisangani as they work to prevent further spread.

The latest update recorded 51 new cases and 20 new deaths over the previous 24 hours. The World Health Organization has warned the outbreak continues to expand, with population movement driving transmission.