The killings were witnessed barely hours after country's Interior Minister Chaudhry Nisar Ali Khan claimed target killings were witnessing a decline in the city.
A man, chairman of a mosque committee, was shot dead in the city's Gol Market Nazimabad.
In another incident, two people were killed when unidentified men opened fire on a rikshaw in New Karachi area, police said. Meanwhile, two policemen were killed in a firing incident.
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