Following Pope Francis' mention in passing of the Uyghurs as persecuted in a new book, the Chinese foreign ministry said the claim is groundless.

"I think often of persecuted peoples: the Rohingya, the poor Uighurs, the Yazidi -- what ISIS did to them was truly cruel -- or Christians in Egypt and Pakistan killed by bombs that went off while they prayed in church," Pope Francis is quoted as saying in the book, "Let Us Dream," according to the AP.

An estimated 1 million Uyghurs, members of a Muslim ethnoreligious group, have been detained in re-education camps in China's Xinjiang region. Inside the camps they are reportedly subjected to forced labor, torture, and political indoctrination. Outside the camps, Uyghurs are monitored by pervasive police forces and facial recognition technology.

Neither Pope Francis nor the Holy See has publicly commented in an official capacity on the situation.

Chinese foreign ministry spokesman Zhao Lijian responded to Pope Francis' mention of the Uyghurs by saying that there was "no factual basis at all" to the pope's comment.

"People of all ethnic groups enjoy the full rights of survival, development, and freedom of religious belief," Zhao said at a daily briefing, according to AP.

Researchers at an Australian think tank found recently that re-education camps in Xinjiang have expanded in the past year, despite reassurances from the government that a majority of detainees had been released.

The Australian Strategic Policy Institute said it had "identified and mapped more than 380 suspected detention facilities in the Xinjiang Uyghur Autonomous Region, highlighting 're-education' camps, detention centres and prisons that have been newly built or expanded since 2017."

The Chinese government has defended its policy of mass detention and re-education as an appropriate measure against terrorism.

A bipartisan group of U.S. senators introduced a resolution in October to declare China's actions against the Uyghur population as a genocide. Sens. John Cornyn (R-TX) and Robert Menendez (D-NJ), who co-sponsored the resolution, emphasized the importance of human rights. 

"For far too long, the Chinese government has carried out a despicable campaign of genocide against millions of Uyghurs and other Turkic Muslims," said Cornyn. "This resolution recognizes these crimes for what they are and is the first step toward holding China accountable for their monstrous actions."

"Stopping a genocide is consistent with our national security and our values, and it starts by standing up and speaking the truth," said Menendez.