Iran claimed Monday it has arrested 17 Iranian nationals allegedly recruited by the Central Intelligence Agency to spy on the country’s nuclear and military sites, and that some have already been sentenced to death. The alleged arrests took place in the Iranian calendar year ending in March 2019 and those taken into custody worked on “sensitive sites” in the country’s military and nuclear facilities, an Iranian intelligence official told a news conference in Tehran.

He didn’t say how many of them got the death sentence or when the sentences were handed down. Iranian state television published images Monday it said showed the CIA officers who were in contact with the alleged spies, the Reuters news agency reports.

In a Monday morning tweet, President Trump called the report of the arrests “totally false.”