COLOMBIAN police believe Australian woman Cassie Sainsbury, arrested for allegedly having an estimated $US1 million worth of cocaine in her luggage, could have been working as a drug mule.
Jorge Mendoza, the ports and airports director for Colombia's anti-narcotic police, says he doubted the 22-year-old's story that she didn't know the drugs were hidden inside 18 headphone boxes.
Sainsbury was arrested at El Dorado International Airport in Bogota on April 12 after a tip-off shewas smuggling 5.8kg of cocaine.
"She could possibly be a drug mule," Mendoza told ABC radio through an interpreter on Tuesday.
"In going through security we found she had 18 packets inside her luggage, which even before opening it we found covered in plastic."
He told the Daily Mail that feigning ignorance was a common tactic of smugglers who were caught.
"Her explanation is not credible. Everyone we catch says they didn't know it was in their luggage, but they know what they were doing."
The Adelaide woman's family insists she is innocent and was set up by a Colombian man she met after arriving in the South American country on April 3 during a working holiday.
Sainsbury's mum Lisa says her daughter is terrified and begging for help as her family fear for her safety in a dangerously overcrowded South American jail.
"I didn't do it mum, you have got to get me out," were the words a hysterical Cassie used in a chilling phone call home after her arrest.
The former personal trainer and ex-Country Fire Service volunteer has spent the past three weeks being shuttled between two Colombian jails.
Ms Sainsbury's fiance Scott Broadbridge was on Monday holed up in their Moana home, south of Adelaide, after receiving negative backlash on social media since news of her arrest broke.
It is also understood Mr Broadbridge, who has spoken to Ms Sainsbury on the phone every night since she was incarcerated, is concerned over what he says is false information being spread about her on social media.
He is believed to be worried about any potential impact public attention will have on her case.
Four cartels run the cocaine market in Colombia and it is understood the family has concerns for Ms Sainsbury's safety.
Ms Sainsbury's sister, Khala, said the family was taking advice from Sydney-based lawyer Jay Williams who has represented asylum seekers at the Manus Island detention centre.
She declined to make further comment upon the lawyer's advice.
It is understood the family was still attempting to contact the lawyer in Colombia who was representing Ms Sainsbury.
The Country Fire Service yesterday distanced itself from Ms Sainsbury, who they said had not been a volunteer since she served for a brigade on the Yorke Peninsula three years ago.
A spokeswoman asked the family to remove the reference to her being a CFS volunteer from their fundraiser page seeking the public's money to pay for her defence.
Cassie's family were forced to defend her from a growing public backlash on social media, saying she was simply "naive" to accept packages from a local man.
"He had been helping her all week, taking her around and showing her places, and just being a nice guy," Ms Evans said.
The family said Cassie wanted to buy headphones as presents for her bridal party and family ahead of her wedding next February.
"She mentioned about these headphones she wanted to get and this man said to her 'I know a guy that if you buy 16 or 18 of them, he can give you a really good price'," Ms Evans said.
The man brought what Cassie believed were headphones to her hotel on the morning she was to leave.
"And this is where the naive bit comes in, she didn't even rip it open to make sure it was headphones in there," Ms Evans said.
Mr Broadbridge also took to social media to defend her from those who don't believe her story. The family set up a fundraising site to raise money for her legal defence, but although it has raised more than $3000, it has also been overrun with comments from doubters.
"If you don't know Cassie, and the respectful, loving, caring person that she is, don't be so negative," Mr Broadbridge said.
"If this happened to your family is this how you'd want people responding to your situation. Just be respectful, we're trying to get an innocent girl back home where she belongs."
Mr Broadbridge said his fiance had travelled to Colombia on a working holiday.
He said she helped manage a commercial cleaning business with national and international clients.
Cassie is now weighing up whether or not she should plead guilty to the drug smuggling charges and hope to lessen a possible 25 year sentence, according to her mum.
Her trial could be two months away and Australian consular officials say they are helping.
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