Sandra Gregory had gone back to Thailand to "tie up loose ends"
Sandra Gregory, the Briton jailed in Thailand for drug smuggling, has been held at Bangkok airport after trying to enter the country, the BBC understands.
She was pardoned by the King of Thailand in 2000 after initially being sentenced to death in 1993.
The 44-year-old, of West Yorkshire, has texted friends in the UK to say she was refused entry to Thailand, despite having a valid visa.
She told them she expects to be deported within 48 hours.
In a text message she said: "I haven't eaten or slept for days. They're telling me I don't get to choose."
Gregory, of Sowerby Bridge, was caught with 86.9g of heroin inside a condom in her body at Bangkok airport in 1993.
The initial death sentence was commuted to 25 years imprisonment after she admitted the charge.
She spent four-and-a-half years in the notorious Klong Prem Prison - nicknamed the Bangkok Hilton - where she had been held in a room with 80 other women, before being transferred to a jail in Kent.
After receiving the royal pardon, she went on to gain a 2:1 honours degree in geography from Oxford University.
Friends said Gregory had gone back to Thailand to "tie up loose ends".
Friend Susan May said: "She said she loves the country despite everything that happened, and she deeply regretted what she did.
"She wanted to go back to visit friends she made in the jail and lay some ghosts to rest."
The British Foreign and Commonwealth Office was unable to confirm any details.