CCTV images show missing ABC employee Jill Meagher talking to a man as she was walking home, minutes before her suspicious disappearance.
Melbourne police say the footage shows the 29-year-old woman walking outside a bridal dress shop in Sydney Rd, Brunswick, about 1.40am local time on Saturday.
It shows a man in a blue top walking back and forth on Sydney Rd. He then starts talking to Meagher outside the bridal store at 1.42am to 1.43am.
She is in high heels and is carrying one or two bags.
He then walks off ahead of her and she waits behind for a moment, then continues walking. The images are the last known sighting of the woman before she vanished. Her disappearance has triggered a homicide investigation amid fears she has met with foul play.
Homicide squad chief John Potter said police had grave concerns for Meagher, who had not been heard of since the early hours of Saturday morning despite widespread media coverage and had not accessed her bank account.
He said the CCTV showed Meagher and six other people, whom they have urged to contact Crime Stoppers.
Police are particularly keen to speak to the man in the blue hoodie, who walked past the CCTV camera twice before talking to Meagher.
"There may be a rational explanation to what's happened but he certainly could help us," Detective Inspector Potter said. One of the men in the footage can be seen looking back and "must have seen something". .
Meagher left Bar Etiquette in Sydney Rd at 1.33am on Saturday.
She then appeared to have crossed Sydney Rd and then started to walk north, Potter said.
He said Meagher appeared to be holding her mobile phone in the footage. "We think she's holding her phone and it's possible she's either about to phone or is phoning someone."
She called her brother in Perth at 1.43-1.45am, just after the footage ends.
Meagher was carrying an ABC bag and her handbag.
The bag was found in a nearby lane on Monday morning and police believe it may have been planted there.
One police theory is that Meagher may have been abducted or had some kind of struggle after the phone call with her brother.
"In fact we're looking more and more at that as a possibility."