Pakistani police say armed men opened fire on a group of transgender people, killing one, in an affluent neighbourhood in Pakistan's city of Karachi.

Aurangzeb Khattak, a police officer, said the shooting occurred overnight on Wednesday. He said passengers in a 4WD vehicle first harassed the group by throwing rotten eggs at them and then opened fire, resulting in the death of Chanda Sharmeeli.

"We are investigating the murder of victim, and from what we can understand so far, is that this was a personal argument gone too far," he told Al Jazeera.

"It doesn't seem like there was a history of animosity."

Khattak said shell casings from a 9mm pistol were found at the scene and that investigators were using surveillance camera footage to trace the 4WD vehicle and arrest the culprits.

Kami Sid, the country's first transgender model and a fellow of Sharmeeli, told Al Jazeera that the men in the car were "drunk" and forced the murdered person to sit in the car with them.

"And as anyone who is being forced to do something, she [Sharmeeli] retaliated and was shot for it," she said, adding that most likely the assailants were from "important families".

"It's time a lesson is learnt, people from big families can't just get away with everything. This society may have found tolerance, but there is no acceptance for the transgender."

The body has been identified and handed over to the family.

Transgender people are known as Khusra or Hijra in Pakistan. In conservative South Asia, where sexual relations outside marriage are taboo and homosexuality is illegal, they are often treated as sex objects and often become the victims of violent assault.

Last week, provisional results from Pakistan's census showed that at least 10,418 people identified themselves as transgender in the country's first official population count since 1998.

According to a government health ministry estimate made in 2015, however, that number is closer to at least 150,000. Read more via Al Jazeera