Three armed men opened fire on guests at a house party in a township south of the South African city of Durban, killing at least 11 and injuring three, police said on Wednesday.

A woman believed to be pregnant and 13 men were among those attending Tuesday’s party in the township of KwaMakhutha in KwaZulu-Natal province, police said.

“Ten victims, including the woman, died at the scene and four were taken to hospital, were one of them succumbed to gunshot injuries,” they added in a statement.

The motive for the attack is not known, but police said initial investigation showed some of the victims were known to authorities, without giving details.

South Africa has one of the world’s highest murder rates, averaging about 60 a day.