South African President Cyril Ramaphosa has announced an audit of unsafe streets "that place women at risk", after the bodies of 12 women were found in just two months east of Johannesburg.

The deaths have sparked a national outcry about the scale of violence against women in a country that has one of the highest rates of gender-based violence in the world.

Ramaphosa also announced plans to reduce alcohol-related violence as part of his multidisciplinary, national emergency response to the murders.

He said gender-based violence could not "be accepted as a normal part of life" and admitted that South Africa had "not done enough" to protect women and girls.

"There has understandably been widespread fear that the discovery of these women in close proximity could indicate the work of a single perpetrator," Ramaphosa said in an address to the nation on Tuesday evening.

"At present, the police have not found evidence establishing that these killings were committed by a single perpetrator."

Four arrests have been made so far.

Admitting the government has not done enough in recent years to prevent gender-based violence, he announced a new wave of measures to help protect women and girls.

"Every municipality must begin a women's safety audit without delay," he said. "High-risk areas must be identified" and addressed.

"These audits must identify broken streetlights, overgrown public spaces, abandoned buildings, unsafe transport routes and facilities, poorly secured parks, and other conditions that place women at risk."

Ramaphosa has also instructed ministers to draw up a plan for an "enforcement package" to reduce alcohol-related violence.

"Alcohol does not cause gender-based violence and it can never excuse it. Responsibility always lies with the perpetrator," he said.

"But harmful alcohol use is a significant aggravating factor in interpersonal violence, and it must be addressed as part of our wider prevention effort."

The South African president also said a deeper change, beyond policing and legislation, must take place to reduce violence against women and girls, saying it "does not begin when a fist is raised" or when a woman is raped or murdered.

"It begins much earlier," he said. "It begins in attitudes that regard women as inferior… with the belief that a man has the right to control a woman.

"It begins when jealousy is mistaken for love, when control is mistaken for protection and coercion is mistaken for affection.

"It begins when a man refuses to accept the word no."

He went on to call on men and boys to take the lead in ending gender-based violence.

"We have placed the burden of male violence on women," Ramaphosa said. "That must change."

"The solution to violence against women cannot be to make women less free."

South Africa has one of the highest homicide rates, with 5,427 people murdered between April and June this year alone.

While South African police statistics do not differentiate victims by gender, the South African Human Rights Commission said recently that 569 women were killed and 1,052 others survived attempted murder between April and June this year.