The mother of two was stopped as she arrived at Bali's Ngurah Rai International Airport on May 19, customs official Made Wijaya said.
He continued: "This is a big international network. The charge against them would carry the death penalty."
Two days after her arrest, Sandiford agreed to be used in a sting operation carried out by Indonesian authorities. When a British woman, identified only as RLD, contacted her two days later a meeting was arranged.
The head of Bali's drug squad said that the woman and two British men, identified by the initials BP and JAP, were subsequently arrested on suspicion of being senior figures in a major drug-smuggling syndicate.
A further 68g of cocaine, 280g of Ecstasy and a small amount of hashish were also seized, officials said.
Yesterday, neighbours of Sandiford in Cheltenham said many "strange" visitors would turn up at the house at all hours of the day and night.
Colin Richardson said: "I was glad to see the back of her. She was totally the wrong sort of person in this sort of neighbourhood."
Another neighbour, who did not want to be named, said: "When the house was repossessed they had to completely redo it.
"She gave the impression of being quite well off and everything, but she was just putting on a facade."
Reports in the local newspaper, the Gloucestershire Echo, revealed that she had clashed with the local education authority over schooling for her son Eliot - who she said had behavioural problems - when he was a teenager.
Neighbours said that in addition to Eliot, who is now believed to be 22, Sandiford had another son, Lewis, who was two years older.
But Maria Swift, 47, who worked part-time for Sandiford, insisted: "She was friendly, bubbly, she was helpful, she helped me. I did a bit of cleaning for her, it was just to help her out in general. Her boys were a bit messy - which boys can be."
At the time she knew Sandiford, she had been working for a firm of solicitors doing administrative work, Swift added.
- Independent
