BEIJING (AP) — An American physician and a colleague were denied a medical visit to an ailing Chinese democracy activist in a jail in eastern China on Saturday, the doctor said.

Dr. Devra Marcus and human rights advocate Kody Kness, both of Washington, were trying to make a humanitarian visit to Zhu Yufu, who is serving a seven-year sentence on a conviction of inciting subversion and is believed to be in poor health.

Kness said their application was denied on the ground that they are foreigners. Marcus said they were briefly held at the prison in Zhejiang province with their passports taken away. She said they were questioned and admonished before they were let go. Photos in Kness’ camera were also erased, she said.

Marcus and Kness have traveled to China on tourist visas.

Zhu is listed among 16 jailed Chinese prisoners that international human rights groups have urged the Chinese government to free. Zhu, 60, is a veteran democracy activist whose latest run-in with the Chinese government was a poem calling the Chinese people into action for freedom.

Bob Fu of the U.S.-based Christian human rights group China Aid said Marcus became concerned about Zhu after hearing reports of his ill health.

In a videotaped interview released by Fu, Marcus said she hoped her visit could help Zhu get medical attention.