A former abattoir worker allegedly strangled and tried to rape another woman a year before he allegedly killed an Indigenous teenager in country NSW.
Warning: This story contains references to and images of an Indigenous person who has died.
Michelle Bright's partially naked body was found dumped next to train tracks less than a kilometre from her Gulgong home, near Mudgee, in February 1999.
After a $1 million reward to crack the cold case was announced on Monday, homicide detectives arrested Craig Rumsby on the outskirts of the town last night.
"His reaction was unexpected — he actually was taken back to the police station with heart palpitations," Detective Superintendent Dan Doherty said.
A post on a Facebook group called "Justice for Michelle Bright" from an account bearing Mr Rumsby's name read: "It's so sad that they haven't caught her killer ... Michelle was like a sister to me I feel sorry for the family".
The lead investigator phoned Lorraine Bright — the mother of the alleged victim — last night to inform her of the breakthrough.
"It has been a long and arduous difficult time for them," Detective Superintendent Doherty said.
"She has been waiting for that phone call for 21 years.
"She can't believe what's happened, but in a good way — she is feeling while they can't get Michelle back, that some justice can be served."
The ABC understands the 53-year-old used to live two doors down from the Bright family at the time, but had recently been living in Windsor, north-west of Sydney.
He was charged with the murder of the 17-year-old, as well as the attempted sexual assault of an 18-year-old girl on New Year's Day in 1998 in Gulgong.
Detective Superintendent Doherty is urging any other potential victims to come forward.
"We believe there may be other victims out there," he said.
The NSW Government reward for information about the case was boosted from $100,000 to $1 million on Monday, but police say it won't be paid out at this stage.
"We are still reviewing all the information coming through, but what I will say is the million-dollar reward certainly enhanced the investigation," Detective Superintendent Doherty said.
Michelle Bright was found in long grass on the side of Barneys Reef Road, three days after she was dropped off by a friend outside at the Commercial Hotel in Gulgong.
Earlier that night, she had attended a birthday party.
Mr Rumsby was refused bail today and will face Mudgee Local Court again next Wednesday.
Lorraine Bright said she was happy with the breakthrough.
"I am overwhelmed, that's all I can say … after 21 years," she said.
