That unidentified gunmen opened fire on a civilian in the Orangi Town area of Karachi on Friday. The victim died on the spot.
The assailants later fled the scene and their whereabouts remain unknown.
Security forces cordoned off the area and initiated a search operation after the attack. However, no arrests have been reported so far.
Earlier in the day, police had recovered a bullet-riddled body in the area.
In another incident, unidentified assailants attacked a man outside his house in the Ramswamy area of Karachi, the capital of Sindh Province and situated 1,150 kilometers (712 miles) south of Islamabad, and shot him dead.
Law enforcement forces cordoned off the area after the incident, and launched an investigation.
Two civilians were also injured in separate shooting incidents in Liaqatabad and Jehangir Road districts of Karachi.
Over 35,000 people have lost their lives in bombings and other militant attacks since 2001 when Pakistan entered an alliance with the US on the so-called war against terrorism, according to local media.
Thousands more have been displaced by the wave of violence and militancy sweeping across the country.
—-Agencies