Where is Liu Xia, 'free' widow of Chinese Nobel winner Liu Xiaobo?
Close friends, and even the artist and poet's lawyer, have not been able to get in touch with her since her husband's funeral.
Where is the widow of Nobel laureate Liu Xiaobo?
The Chinese authorities say Liu Xia, the widow of Nobel laureate Liu Xiaobo, is a free woman.
But when we tried to visit her apartment in Beijing, we were immediately surrounded by security guards, who pushed and shoved our team, yelling at us to "Get out!"
One of the men grabbed my hand so hard he broke the skin, leaving the bleeding imprint of his thumbnail behind.
They jostled our cameraman, covering his lens with their hands, and ordering him to stop filming and leave.
Liu Xia has been held under what amounts to house arrest in this compound since her husband was awarded the Nobel Peace Prize in 2010.
Despite never being accused of committing any crime herself, she has lived the last seven years in almost complete isolation, broken only by monthly prison visits, supervised grocery trips, and very occasional brief contact with friends.
Her sentence does not appear to have ended with the death of her husband.
When I asked the guards whether Liu Xia was at home, and where she was, they claimed ignorance, asking "Which Liu Xia?" and whether we had made an appointment to see her.
Then they resumed shouting at us to "get out quickly" as one of the men threatened to confiscate our camera.
As we left, we noticed a police car pulling up behind us and following closely until we were out of the area.
Liu Xia was last seen in images released by Chinese officials after the death of her husband earlier this month.
The photographs show Mrs Liu being comforted by her brother at the funeral and then looking down at the water as her husband's ashes were scattered at sea.
But after the pictures were taken, she disappeared.
Close friends, and the couple's lawyer, say they are still unable contact her, and believe she remain under the authorities' control.
There is a rumour she has been taken to southwest China by police, but wherever she is, she has made no contact with the outside world.
Sky News showed the images to Dr Yang Jianli - a long-time friend of the couple, who has spent time in a Chinese prison himself, and now lives in exile in the United States.
"This is really heartbreaking," he said quietly as he looked through the photos.
He pointed out the close family members by the side of the casket in one image, but could not identify the other supposed mourners looking on.
"I don't think any of them is a close friend of the family," Dr Yang said, "I think they are government officials, to be there to make sure everything is under control."
He is now desperately worried about Liu Xia, and called for the international community to press China for her immediate release.
"This is very urgent. She has been very ill herself, both physically and mentally. She suffered very serious depression and a heart attack a few years ago."
"I was so worried and still worry that she would not be able to survive."
Dr Yang stressed that Liu Xia was a poet and an artist, who had never sought conflict with the Communist Party.
"She is not a fighter, she is a lover," he explained. "She loved her husband fully and was devoted to her husband fully.
"She has a very delicate, fragile personality, she is a poet and she would not challenge the authorities, she is not that kind of person."
Human Rights Watch has called for her release and Amnesty International has started a 'Free Liu Xia' petition, which states: "especially now that her husband has passed, it's time the Chinese authorities stop cruelly punishing Liu Xia".
We put the case to China's Ministry of Foreign Affairs in Beijing.
"If Liu Xia is a free woman," I asked, "Why can't she speak to her friends or leave China?"
"I do not know the information you mentioned, the ministry's spokesman Lu Kang replied, "and this is not a diplomatic question. Next question."
My question was later redacted from the official transcript.