Small groups of protesters in cities across the United States are camping outside offices used by federal immigration agents, seeking to disrupt deportations in response to U.S. President Donald Trump’s tough stance on illegal immigration.

The protests, which began last week in Portland, Oregon, were spurred by news and images of migrant children from Central America being separated from their parents after crossing the U.S. southern border under Trump’s “zero tolerance” immigration policy, organizers said.

The protests have since spread to New York City, Detroit, Los Angeles, San Diego and Chicago, among other cities, causing minor disruptions to immigration officials, and in some cases criticized as well meaning but misguided by immigrant rights groups.

The administration of President Donald Trump has faced fierce criticism for separating more than 2,000 children from their families in order to prosecute their parents for crossing the border from Mexico illegally. Trump backed down last week, signing an executive order to keep families together in detention during immigration proceedings.