US authorities have arrested 538 undocumented immigrants and deported hundreds in a mass operation, President Donald Trump’s spokeswoman said just days into his second term, AFP reported.

In an Instagram post late Thursday, Caroline Leavitt said the Trump administration had arrested 538 undocumented criminal immigrants, adding that “hundreds” had been deported on military aircraft.

Trump promised a crackdown on illegal immigration during his election campaign and began his second term with a series of executive orders aimed at overhauling the process of entering the US.

He has signed orders declaring a ‘national emergency’ at the southern border, announced the deployment of more troops to the region and vowed to deport ‘criminal aliens’.