ICE set to begin immigration raids in 10 cities on Sunday

(CNN)Immigration and Customs Enforcement is pressing forward to arrest and deport families with court-ordered removals in 10 cities beginning Sunday, according to a senior immigration official, after President Donald Trump's tweet revealing an operation was imminent.

But acting Department of Homeland Security Secretary Kevin McAleenan has been hesitant about elements of the operation, according to two sources familiar with his thinking.

ICE has said it was considering options to arrest and deport families who have gone through their legal proceedings but has refrained from publicly providing the scope and timeframe of the operation, which officials say could lead to a situation where a family is separated and could cause a backlash against the department.