A regional group called Mohajir Sooba Tehreek has been pushing for the creation of a separate province for the Mohajirs, an Urdu-speaking group, but Sindhi nationalists, led by the Awami Tehreek political party, oppose the idea.
On Tuesday, rally participants were marching from the Lyhari district of Karachi to the governor's palace when gunmen opened fire, Gulf News reported.
Ayaz Latif Paleejo, the leader of Awami Tehreek, told the Pakistan Daily Times that the protesters were unarmed when the gunmen attacked.
Masked armed men appeared from the streets of Lea Market and its adjoining areas, and opened straight fire on the participants of the rally, injuring several ladies, children and young men and some of them were killed, he said.
Paleejo was careful not to blame members of the Mohajir community, as many do not favor secession from the province.
We believe that the entire Urdu-speaking community does not support [the] Mohajir province [secession] demand, as they believe that they are the part of Sindhi nation, Paleejo said.
The Mohajirs are Muslims who first migrated from India to Pakistan in large numbers following the Indian Partition of 1947. Many ended up in Sindh Province, which includes Karachi, a bustling port city and the region's economic hub. Though they share the same religion as most Sindh inhabitants, the Mohajirs spoke a different language and were accustomed to a more urban lifestyle than the region's native inhabitants.
Integration was challenging for both sides. As the Mohajirs moved in great numbers to Sindh's biggest cities, tensions grew between the urban Mohajirs and the rural Sindhi communities.
In recent months, that tension has intensified. Mohajir Sooba Tehreek has organized several rallies to push for a separate province, arguing that Mohajirs have been marginalized by the Sindhi population. There has also been an increase in pro-separation graffiti on walls and buildings throughout Karachi.
On Sunday, officials from Pakistan's ruling political party condemned the movement to establish a new province for Mohajirs, calling it a conspiracy aimed at exacerbating political tensions.