Two men questioned over the murder of Lisa Dorrian gave different accounts of a call said to have been made after she disappeared, the BBC has learned.
Lisa Dorrian's body has never been found
One account emerged during lengthy police questioning - the other was given to the BBC's Spotlight programme.
One man, who claims to have been the last person to see the 25-year-old, told the programme he called her mobile moments after she disappeared.
He claimed it was answered by her boyfriend who said he was in Bangor.
When questioned by police the man who answered the call said he was in a flat in Ballywalter.
Ms Dorrian disappeared after a party in a caravan park in Ballyhalbert more than three months ago.
Just over a week ago BBC Spotlight reconstructed the account of events given by the teenager who claims he was the last person to see Lisa alive.
According to his version of events, at about 0500 GMT on Monday, 28 February they were frightened by noises outside the caravan where they were partying.
But his explanation of exactly what frightened them was vague. He claimed they ran from a caravan and that in the dark he lost Lisa.
Minutes later he said he called her mobile phone but she did not answer. Instead he spoke to her boyfriend who, he claimed, told him he was in Bangor with another woman.
But BBC Northern Ireland Security Editor Brian Rowan said during questioning at Antrim police station the man who answered Lisa's phone told detectives a different story.
Lisa disappeared after a party at a caravan
During two days of questioning he said he was with another man and a teenage girl in a flat in Ballywalter.
The man claimed Lisa's phone had been left in the flat, and that was why he answered it.
He claimed that when he called the teenager gave no indication that anything was wrong.
He told the police the teenager was not distressed or panicked but sounded completely normal.
But the man told the police that later that day he met the teenager in Ballyhalbert.
The man claimed that at that point the teenager appeared emotionally distressed, shaky, tearful and not himself.
Following the Spotlight programme there have been a number of developments, Mr Rowan added.
"It's my understanding that in the past few days there have been two meetings at Belfast City Hall," he said.
"These followed approaches to the loyalist politician David Ervine.
"Several allegations were made. One, that just a couple of weeks before her disappearance, Lisa was being harassed by two men over claims that she owed them money for drugs.
"And a second allegation that she was minding £20,000 at her Bangor flat for another man. Details of these allegations and the names that were given to David Ervine have now been passed to the police."