A diarrhea outbreak has claimed at least 30 lives in South Africa, authorities said on Monday.

All the deaths were reported in the city of Ethekwini, the KwaZulu-Natal Province, the Ethekwini Communicable Disease Service Department said.

The deaths occurred between May and June, When the city's Prince Mshiyeni Hospital alone reported 22 deaths, the department said.

An investigation has been launched into the cause of the epidemic.

Tests have found a virus that causes severe diarrhea, but the virus is not identified, according to the South African Broadcasting Corporation.

A consolidated report will be released to the public as soon as findings are collated, said Ayo Olowolagba, head of the department.

He said they want to find out what the real problem is and look at avoiding similar incidents in the future.

Olowolagba urged the public to take precautionary measures, including ensuring personal and environmental hygiene.

If there is any case of diarrhea, he warned, dehydration should not be allowed to happen.