Qandeel Baloch, a social media star whose exploits divided opinion in conservative Pakistan, was allegedly strangled by her brother in what appears to be an "honour killing", police and her family say.
Ms Baloch's raunchy social media photos challenged social norms in Pakistan, a deeply traditional Muslim country where women are often repressed by their family or the community.
Her killing has shocked the South Asian country.
Ms Baloch received multiple death threats and suffered frequent misogynist abuse, but continued posting provocative pictures and videos.
In Facebook posts, she spoke of trying to change "the typical orthodox mindset" of people in Pakistan.
Punjab Police spokeswoman Nabeela Ghazanfar told Reuters Ms Baloch, real name Fauzia Azeem, was killed on Friday night in her family home on the outskirts of Multan, a large city in Punjab province.
Ms Baloch's body was discovered on Saturday and her father Muhammad Azeem told the police that his son Waseem had strangled her, Mr Ghazanfar said.
"Apparently, it is an honour killing but further investigations will reveal the real motives behind this murder," Mr Ghazanfar said.
Ms Baloch's father told local media his son Waseem had stayed overnight at the family home and quarrelled with Ms Baloch over money issues and her risque photos.
Police said they were looking for Waseem, who had disappeared.
Ms Baloch had struggled to reconcile her family's conservative values with her social media stunts, including a selfie with a famous Muslim cleric that led to widespread condemnation from powerful religious figures.
In the days before her death, she had told local media she was concerned about her safety.
Ms Baloch's death sparked an outpouring of grief on Twitter and other social media websites and reignited a debate about honour killings in Pakistan.
More than 500 people -- almost all women -- die in Pakistan each year in such killings, usually carried out by members of the victim's family meting out punishment for bringing "shame" on the community.