Iran claims it will pardon a “large number” of prisoners to mark the upcoming 40th anniversary of the Islamic Revolution, though how many of those locked up might actually get out remains an open question, according to Sky News.

State TV in Iran has not confirmed the exact figure, but some reports have said as many as 50,000 prisoners would either be freed, or have their sentences reduced.

If true, that number would represent about 20 percent of the estimated 250,000 prisoners in Iran. Among those prisoners are a huge number of political prisoners, according to human rights groups and Iranian exiles.

How many of those held for political beliefs or activity might be released is also unknown. It’s a particularly hard question to answer, because Iranian officials claim there are no political prisoners.

Judiciary Chief Ayatollah Amoli Larijani made that claim Monday, where he reportedly referenced the 50,000 who might be released. Dismissing the calls for the release of people held because of their opposition to the regime, he said “we currently do not have such prisoners.”

AMERICAN NAVY VETERAN HELD IN IRANIAN PRISON SINCE JULY ON UNSPECIFIED CHARGES

Another question is how many dual citizens being held by Iran might be released. Several of those jailed have nationality with Western nations, and are being held on a variety of charges related to national security.

Among those being held is Michael White, an American detained in Iran last July on security-related charges. White, a 46-year-old U.S. Navy veteran, was arrested because of a “private complaint” against him. White was detained in Iran after visiting his Iranian girlfriend, his mother told the New York Times. Joanne White said her son was scheduled to return to the U.S. from Iran through Dubai in the United Arab Emirates on July 27, but her son never boarded his flight.

President Donald Trump has warned that Iran would face “new and serious consequences” if it continued to hold U.S. citizens unjustly.

The mass release of prisoners would have to be approved by Supreme leader Ayatollah Ali Khamenei.