Muttahida Qaumi Movement (MQM) has announced to observe a day of mourning on Thursday across Sindh against killing of the party workers.
The MQM has urged the transporters and businessmen to support the mourning call and close their business activities and transport.
Earlier this morning, at least four MQM workers were killed in a firing incident in Malir.
According to details, unknown men opened at a hotel located in Jam Goth area of district Malir in which the activists were killed.