DUBAI, United Arab Emirates — Iranians angry over rising food prices and inflation protested in the country’s second-largest city and other areas Thursday, putting new pressure on President Hassan Rouhani as his signature nuclear deal with world powers remains in peril.

The police in Mashhad made an unspecified number of arrests, local authorities said, though the country’s powerful Revolutionary Guard and its affiliates did not intervene as they have during other unauthorized demonstrations since Iran’s disputed 2009 election.

It wasn’t immediately clear how many people took part in Thursday’s protests, though social media posts suggest several thousand demonstrated at rallies across at least three other cities.

Iran’s state-run IRNA news agency quoted Mashhad’s governor, Mohammad Rahim Norouzian, as saying there was an illegal gathering there.