Unidentified gunmen opened fire at Akram aka Shahji in Ghaziabad area of Orangi leaving him dead on the spot.
The deceased was said to be a worker of a political party.
Armed men shot dead another man at Rehmat Chowk of Baldia Town within a span of one hour from the first killing.
Paramilitary Rangers arrested five suspects in raids in different parts of Karachi.
Rangers spokesman in a statements said that the raids were conducted in Sharafi Goth, Zaman Town and Karnal Basti areas. Five suspects arrested with hand grenades and other munitions.
Police also conducted raids in Khuda Ki Basti in which 20 accused were arrested, which were transferred to undisclosed place for interrogation.
Six armed men robbed four million rupees from a private bank branch at Shaheed-i-Millat Road of Karachi.
The accused entered in the bank after injuring security guards and snatched four million rupees from the bank.
Police says the security arrangements at the bank were not satisfactory.
The investigators have collected evidence and CCTV footage from the bank.