At least three persons, including a woman, were gunned down in different areas of the city on Sunday, officials said.
The death toll has mounted to six in last 24 hours.
Law enforcement agencies seem to have failed in controlling ongoing violence in the city with people losing lives on a regular basis.
A political activist, Safdar, was shot dead by unidentified gunmen in New Karachi. The gunmen escaped from the scene after killing him.
A 30-year-old Khurram was killed in a firing incident near Gol Market, Nazimabad.
A man was gunned down at Yousuf plaza area.
Meanwhile, police arrested more than 15 suspects involved in different crimes from Mawachko.