The Home Office was condemned last night over its decision to deport an asylum seeker and her two-year-old son back to China after five years living in Scotland.

Angry friends and supporters of trade unionist Qin Wang raised a campaign to stop her removal from the UK - as she and her son Jian Qi Lin were on their way from the Dungavel detention centre in Lanarkshire to be held near Heathrow where she is due to be flown on a Russian Aeroflot plane tomorrow.

Friends say Qin Wang, who has been living in Sandyhills, Glasgow, talks of killing herself rather than returning to China where she says she was beaten and indecently assaulted by police when detained in connection with her union activities - outlawed by the Chinese authorities. The woman, who gave birth to her son in Glasgow, is said to have suffered torture before managing to escape one of the many political prisons in China after her arrest for being a union official.

Her solicitors say the Home Office has taken issue with Qin Wang "going underground" for four years after first registering as an asylum seeker in 2003.

She re-registered in 2007 - but after a series of appeals she failed to convince the Home Office of her credibility.

After being detained without notice by the Home Office on Friday she has not eaten for three days while at Dungavel.

But it emerged yesterday that a diplomatic complication could delay or even halt the deportation before it has even started - because the Chinese authorities are understood to have resisted having her back.

Qin Wang, an English student at the Glasgow Metropolitan College, has no official Chinese identity papers or passport - and her representatives say the Chinese are unlikely to accept her without those documents.

Friends and the boy's father, Qin Wang's estranged boyfriend, a Chinese asylum seeker who lives in Glasgow, have visited her in detention.

A close friend, Jing Wu, from Glasgow said: "It is a very bad experience for them. It has all happened so quickly and I don't think there is anything we can do now.

"She is quite calm and doesn't fight with anyone but she got handcuffed when she was being taken away.

"She does cry and has refused to eat. She says she might kill herself and will try her best not to go on the plane. The boy is very quiet."

Phil Jones, of the Unity Centre, the Glasgow-based outfit which supports asylum seekers and refugees, said there was concern at the Home Office action coming at a time when Chinese authorities have launched a major crackdown on dissent in the run-up to the Beijing Games.

"We don't think it is right that she should be treated in this way by the British authorities," he said. "The real issue is she absconded for so long.

"This is the problem with Chinese in particular, they are very scared of how things work and scared of the authorities in particular as they come from a completely state-controlled situation. "

The Chinese Communist Party's authoritarian rule has banned all trade unions and unofficial religious groups, including the Falun Gong spiritual movement, which was outlawed in 1999. Members have been tortured, imprisoned and subjected to psychiatric abuse, human rights groups say.

Qin Wang had been working in a factory in south-east China which was closed without any of the workers getting paid their legitimate redundancy payments. When Qin tried to agitate about this she was arrested by the authorities and jailed for three months.

The Home Office makes a policy of not commenting on individual cases.