In gloomy corridors outside a Manhattan courtroom, masked agents target and arrest migrants attending mandatory hearings — part of U.S. President Donald Trump's escalating immigration crackdown.

Trump, who campaigned on a pledge to deport many migrants, has encouraged authorities to be more aggressive as he seeks to hit his widely reported target of 1 million deportations annually.

Since Trump's return to the White House, Homeland Security agents have adopted the tactic of waiting outside immigration courts nationwide and arresting migrants as they leave at the end of asylum hearings.