Three gunmen opened fire at a house party in a township south of Durban, South Africa, late Tuesday, killing 11 people including a woman believed to have been pregnant, police said Wednesday.

The attackers entered a house in the Ziko area of KwaMakhutha township, about 30 kilometres south of Durban, and shot at a group of people who had gathered for a party, according to police. Ten victims died at the scene and an eleventh died later in hospital. Three others were wounded; police did not immediately give details on their condition.

Acting National Police Commissioner Puleng Dimpane said investigators were following "a promising lead," though a motive has not yet been established. Police said some of the victims had previously come to the attention of Crime Intelligence over alleged illegal activities, without elaborating further. No arrests had been made as of Wednesday, and police have launched a manhunt for the attackers.

Wednesday's attack is the latest in a string of mass shootings in South Africa in recent months. In June, multiple gunmen killed 12 people in an informal settlement in a Johannesburg suburb, an attack police linked to criminal gangs. Two separate mass shootings two weeks apart in December killed 21 people combined, also carried out by multiple gunmen.

South Africa has among the highest violent crime rates in the world. Official police figures recorded 5,427 homicides between April and June this year, an average of nearly 60 a day. Shootings are the most common method of killing in the country, and police and crime researchers have long pointed to a large number of illegal firearms in circulation as a central driver. The army has been deployed to assist police in combating violent crime in some areas.