An Iranian court has sentenced an Iranian-American businessman and his elderly father to 10 years in prison on charges of cooperating with the United States, the Iranian judiciary’s official news website reported on Tuesday.

Iran’s Islamic Revolutionary Guard Corps detained Siamak Namazi, a businessman with dual U.S.-Iranian citizenship in his mid-40s, in October 2015, while he was visiting family in Tehran. The IRGC arrested his father, Baquer Namazi, 80, a former UNICEF official and also a dual citizen, in February.

Both men have been sentenced to 10 years in prison “for cooperating with the hostile government of America,” the Mizan website said, citing “an informed source.” It did not specify when exactly the sentences had been handed down.

The sentences are the latest sign of an intensifying crackdown against Iranians with ties to the West directed by hardliners who are powerful in Iran’s judiciary and security forces, in the aftermath of Iran’s historic nuclear deal with the United States and other world powers last year.