Johannesburg - The city of Johannesburg has completed the recruitment of 1 500 additional metro police officers who are currently undergoing training to help fight crime, mayor Herman Mashaba said on Wednesday.

Mashaba, whose Democratic Alliance wrested control of the city from the ruling African National Congress after 2016 municipal elections by forming an alliance with other smaller parties, said the Johannesburg Metrol Police Department (JMPD) had effected over 20 000 arrests since the multi-party government came into office.

"It is worth noting that this is more arrests than were achieved between the years 2009 to 2012 combined," he said in a speech on the state of the city.

These included 577 people arrested in connection with "hijacked" properties, including undocumented immigrants, he added.

"Many people from across the continent and world, seek a better life in South Africa, and Johannesburg in particular," said Mashaba, who has denied charges of being biased against African immigrants.

"The reality of our city is, that many undocumented immigrants, are forced to live on the fringes of our society with limited protection afforded to them.