Happening now, Columbia University student detained the senior about to become a U.S. citizen,

now detained but not charged by immigration officials. News seen in reporting straight ahead.

And Harvard hits back. The Ivy League University refusing to bow to the Trump administration's demands the billions of dollars in funding at stake.

Welcome to our viewers here in the United States and around the world.

I'm Wolf Blitzer with Pamela Brown and you're in the Situation Room.

We begin this hour with the Trump administration testing the power of the presidency over the issue of immigration.

A Palestinian student arrives for a final U.S. citizenship interview and is paraded out in handcuffs.

His attorney says he's a legal U.S. resident and is being tapped for his pro-Palestinian

activism over at Columbia University. Also this afternoon, a court hearing is scheduled for

this Maryland father who was mistakenly deported and now sits in a notorious Central American

prison. And both the White House and El Salvador's president are defying orders to return him to the United States.

We're covering all of the angles.

CNN White House reporter Elena Trine previews the hearing and the stakes.

And correspondent Gloria Pasmino begins with the arrest of the Columbia University student.

Gloria, has the student been charged with anything?

No, Wolf. He has not been charged with any crimes so far,

but the Trump administration appears to be using the same portion of the U.S. immigration law

they've used to target other student activists. Now, Medawi has been a permanent

U.S. resident for 10 years, but the administration is moving to cancel his green card, citing

the Immigration and Nationality Act of 1965. That gives the Secretary of State wide powers to

deport people if they are deemed to be a foreign policy threat.

Now, we do not know what the threat is in this case, but we do know that Medawi is a prominent

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