The marriage between a local Christian woman and a Chinese Christian man six months ago in the eastern Pakistani city of Faisalabad had all the signs of a perfect match.

She was 19, he was 21. She was a trained beautician, he a businessman selling cosmetics.

Her family didn’t have much money but the groom generously offered to pay all the wedding expenses.

The proceedings took place in strict accordance with Pakistani customs. This pleased her parents, who felt that their daughter’s new Chinese husband respected local traditions.

There was a formal proposal, followed by a henna ceremony, and finally the “baraat”, where a procession arrives at the bride’s house, vows are exchanged and the bride leaves to start a new life with her husband.

But within a month, the woman, who only wants to be known as Sophia to protect her identity, would be back at her parents’ home. She escaped what she now believes was a racket to traffic Pakistani women into a life of sexual servitude in China.

Saleem Iqbal, a Christian human rights activist who has been tracking such marriages, said he believed at least 700 women, mostly Christian, had wed Chinese men in just over a year. What happens to many of these women is unknown but Human Rights Watch says they are “at risk of sexual slavery”.

In recent weeks, more than two dozen Chinese nationals and local Pakistani middlemen, including at least one Catholic priest, were arrested in connection with alleged sham marriages.

Pakistan’s Federal Investigation Agency (FIA) told the BBC that “gangs of Chinese criminals are trafficking Pakistani women in the garb of marriage into the sex trade”. It said one gang posed as engineers working on a power project while arranging weddings and sending women to China for fees ranging from $12,000 to $25,000 per woman.

Christian women – who come from a mostly poor and marginalised community – are seen to be particularly targeted by traffickers, who pay their parents hundreds or thousands of dollars.

China has denied that Pakistani women are being trafficked into prostitution, saying that “several media reports have fabricated facts and spread rumours”.

But it admitted this week that there had been a surge in Pakistani brides applying for visas this year – with 140 applications in the year to date, a similar amount to all of 2018. A official from the Chinese embassy in Islamabad told local media it had blocked at least 90 applications.

‘Imbalanced society’

A rise in cases of suspected bride trafficking from Pakistan to China has come amid an unprecedented influx of tens of thousands of Chinese nationals into the country. China is investing billions of dollars in the China-Pakistan Economic Corridor (CPEC), a network of ports, roads, railways and energy projects.

The two countries are close allies and a visa-on-arrival policy for Chinese nationals has also encouraged entrepreneurs and professionals not directly linked to CPEC to flood into Pakistan.