After 30 years of investigation, detectives were able to arrest a man in Birmingham over the disappearance of Harbans Kaur Lally.
She was 19 when she disappeared in 1985 from Leeds.
Investigation has revealed new information and the police have now launched a full scale murder investigation.
A 53 year old man was arrested by West Yorkshire Police on suspicion but has now been released under investigation.
A woman aged 74 was arrested on suspicion of conspiracy to murder, another man in his late seventies was arrested on suspicion of murder. They were released on bail till investigation is completed.
Harbans Kaur Lally was born and bought up in Rugby. She got married in Rugby in 1984 and later on moved to Leeds.
Harbans Kaur Lally gave birth to a daughter in a hospital in Leeds. She worked for the Burton Group till mid-1985.
It is believed that she came back to her home town Rugby, and went to India and has not been seen since.
Police carried out a door to door search operation in the street where she lived at the time.
Det Chief Insp Nicola Bryar, of West Yorkshire Police, said: “We have recently received information that raises concerns about Harbans’s apparent disappearance, which we are now treating as a murder investigation.
“We are trying to build up a picture of her life at the time she disappeared and we are very keen to hear from anyone with any information that could assist us.
“We would like to speak to anyone who knew Harbans, who was also known as Susan, when she lived and worked in Leeds in 1984 to 1985, and also anyone who knew her when she was growing up in Rugby, either through school or in the area she lived.
“We are particularly interested to speak to anyone who knew her when she returned there in 1985.
“We would like to reassure people that we will treat all information in the strictest confidence and would urge anyone who does know something that could assist the investigation to contact us.”
Anyone with information should call West Yorkshire Police Homicide and Major Enquiry Team via 101 quoting Operation Parryton or Crimestoppers, in confidence, on 0800 555 111.