Mum-of-two Mumtaz Sattar died in the country's Punjab province last month. At a press conference, Mrs Sattar's sister Mehnaz Jilani, 29, from Glasgow broke down as she spoke of her family's heartache.
Flanked by her two sisters and brother, she said: "These past three weeks have been full of shock and disbelief for the whole family.
"Our sister would always take care of us all and keep us right.
"Our sister never deserved this horrific attack and all behind it should be given the upmost sentence there is.
"Our main focus is on our two nieces now
"A big part of our family life is now gone. No more visiting each other. No more phoning each other. No texting each other. No more going out. No more big sister. All we are asking for is justice."
Abdul Sattar, 40, the husband of Mumtaz Sattar was arrested by police investigating her death along with three other men - according to a lawyer acting for the family.
Solicitor Aamer Anwar said Mr Sattar is being held in custody at Nankana District Police Office.
The couple, who were married for 14 years and have two daughters aged 10 and 13, were on a trip to Pakistan to visit Mr Sattar's family when the death occurred.
Mr Sattar, who ran a newsagents in Port Glasgow, told police they were drugged, attacked and robbed by two men on a taxi ride, on September 21.
He said they were thrown out of a moving car and his wife died from head injuries.
She was buried days later. But the family say they do not believe his version of events and - backed by their legal team, Governor of the Punjab region, former Glasgow MP Mohammad Sarwar, and Humza Yousaf MSP - they are calling for justice.
First Minister Alex Salmond and officers from Police Scotland are also said to have assisted the family.
Mr Sattar and the other three men arrested are expected to spend 14 days in custody before formal charges are brought.
Mr Anwar told the press conference: "I can advise that Abdul Sattar has now been formally arrested and is in custody at Nankana district police office.
"Three other suspects have also been arrested. These men who were on the run following the recovery of a white car on Sunday are allegedly linked to the white car and to Abdul Sattar.
"Critical to the investigation has been the recovery of the white car which Mr Sattar claimed was a taxi and used to transport him and Mumtaz from outside the security perimeter of the airport in Lahore. Police have confirmed this car is not a taxi and that Mr Sattar was seen on CCTV from the airport greeting the males from the car."