"The four persons gunned down today belonged to the Hazara community and ran junk shops in the local Kabari market," Quetta police official, Riasat Ali said.
"The attack appears to have been sectarian motivated as four men on motorcycles came and fired on the four and raced away," he said.
In another incident, a member of a polio team was shot and killed by gunmen in Rind Garh area of Quetta, police said.
Gunmen riding a motorcycle fired at the team while it was administering anti-polio drops to children. One member of the team was hit by bullets and died while being taken to hospital.
Meanwhile, in Karachi, five workers of the banned Ahle Sunnat Wal Jamaat (ASWJ) said to be an offshoot of the Sipaha Sahaba group were gunned down in two separate incidents.
Police said four of the ASWJ activists including two brothers were killed in Gulshan-e-Iqbal on Monday evening while another activist of the party was shot dead in Gulberg.
In another incident an activist of the Sunni Tehreek was shot dead in New Karachi.
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