An Iranian man wears a protective face mask, following the coronavirus outbreak, as he walks in Tehran, March 5, 2020. Photo: WANA (West Asia News Agency) / Nazanin Tabatabaee via Reuters.

Iran expressed concern on Wednesday about the health of imprisoned Iranians in the United States amid the coronavirus outbreak, a day after Washington called on Tehran to free detained Americans.

Iran, the fourth worst-affected nation after China, South Korea and Italy, has temporarily freed about 70,000 prisoners to help curb the epidemic.

That prompted calls from the United Nations and the United States for political prisoners, including dozens of dual nationals and foreigners held mainly on spying charges, to be released from overcrowded and disease-ridden jails.

“The United States will hold the Iranian regime directly responsible for any American deaths,” US Secretary of State Mike Pompeo said in a statement on Tuesday.

In response, Iran’s Foreign Ministry said Tehran had similar concerns about several dozen Iranians held in US prisons, mostly for violating sanctions.

“The state of America’s prisons and their health situation are worrying … we are ready to bring the jailed Iranians in America back to Iran,” spokesman Abbas Mousavi told an online news conference.

“American officials should pay serious attention to the health conditions of the Iranians who have been taken hostage in America. They have been imprisoned without any legal basis.”

In his statement, Pompeo noted “deeply troubling” reports that the coronavirus had spread to prisons and said any nation offering aid to Tehran should seek a reciprocal humanitarian gesture of releasing prisoners.

“The Iranian regime recently released 70,000 prisoners due to the outbreak of COVID-19, demonstrating its ability to grant clemency and show mercy. Yet it continues to unjustly detain several American citizens, without cause or justification,” he said.

Washington has long demanded Iran release American citizens including father and son Baquer and Siamak Namazi, Navy veteran Michael White and former FBI agent Robert Levinson.

Frictions have risen between Iran and the United States since 2018, when Washington quit Iran’s nuclear deal with the West and reimposed economic sanctions.

Tehran denies it holds people on political grounds, and has mainly accused foreign prisoners of espionage.