The daughter of a Hong Kong-based bookseller detained in China on Tuesday appealed for U.S. help in pressing China for information about his status and securing his release.

Angela Gui told the Congressional-Executive Commission on China that her father, Gui Minhai, a naturalized Swede, had been detained for eight months without trial and was being denied consular access or legal representation.

"I still haven't been told where he is, how he is being treated, or what his legal status is — which is especially shocking in light of the fact that my father holds Swedish, and only Swedish, citizenship," she said.