Police on Wednesday launched an investigation into the murder of a social activist who was stabbed to death in the New Karachi area a day earlier.

Saba Aslam, 27, was attacked outside her home in Sector 5-J of New Karachi near Aqsa Masjid on Tuesday when she came out early in the morning to run an errand.

Bilal Colony police have registered a case under Section 302 (murder) of the Pakistan Penal Code against a neighbour of the victim, Ghazanfar alias Maan, on behalf of the state through a police officer.

Aslam's murder also echoed on social media, where users demanded that her killer be arrested using the hashtag #JusticeForSabahAslam.

According to the First Information Report reviewed by Dawn.com, Aslam was stabbed to death near Monotechnical College in New Karachi. Two eyewitnesses namely Akhlaq Ali and Zeeshan Shaukat told police that the woman was allegedly killed by their neighbour, Ghazanfar, who managed to escape from the crime scene.

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The victim’s brother, Mohammed Yasir, and her sister, Sadaf, told police that they did not want any legal proceedings and even showed reluctance to lodge the FIR.

“She was murdered over some personal enmity and after an exchange of hot words,” said the FIR.

Central SSP (Investigation) Shahla Qureshi said the initial probe had revealed that the murder took place over "throwing of garbage on the street" in the neighbourhood.

Bilal Colony Station Investigation Officer (SIO) Arif Shah told Dawn.com that police had lodged the FIR on behalf of the state through a police officer as the family had refused to lodge a case. However, he said, Aslam's relatives, who were in a "state of shock" initially, had now shown interest in pursuing the case legally.

According to the SIO, the "last dispute" between the victim and the suspect was apparently over throwing garbage on the street, but police were also investigating other possible motives for the murder.

The officer revealed that the alleged killer was stated to be addicted to charas (hashish), while the victim was a known social activist in the area.