A young Taiwanese man on a business trip to Shanghai was pulled aside at the border and grilled for six hours by plainclothes officers over his past job at Amnesty International — a warning sign for anyone with human rights ties who travels to China.

• He was taken to a closed room by three plainclothes officers, pressed to unlock his phone, and had his photos, email and chat apps searched.
• Questions focused on his old work: what he did at the organisation, whether he wrote about Xinjiang, Tibet or Hong Kong, where its money came from, and which politicians he knew.
• He downplayed his role, said he had already left the job, and finally gave up on entering China altogether so he could fly home safely.
• China's Taiwan Affairs Office confirmed the case and called the questioning entirely legal, describing Amnesty as an anti-China group.
• Taiwan's Mainland Affairs Council says Beijing has gone after people years after they left political or rights work, and told citizens not to assume old jobs are forgotten.

Outlook: Expect more Taiwanese travellers with rights or activist backgrounds to be stopped at Chinese borders, and more warnings from Taipei against making the trip.