A Taiwanese woman's Chinese husband disappeared three days after receiving his Taiwan ID card, and the government admits these cases are real — bad news for Taiwanese who marry across the strait, and a fresh security worry.

• A woman went to the immigration office asking for help after her Chinese husband vanished once his ID came through and cut off all contact.
• Police found him but said they could do nothing, because an adult is free to refuse contact.
• Taiwan's Mainland Affairs Council confirmed such cases exist, but said a marriage lasting six or seven years can't simply be called fake.
• Chinese spouses must live in Taiwan for six years before getting an ID card, and immigration officers screen for sham marriages at the airport interview.
• Officials say some cases still slip through and promise a review of the process, while warning against tarring all cross-strait marriages.

Outlook: Taiwan is likely to tighten checks on cross-strait marriages as national security concerns grow, without changing the six-year residency path.