Sen. Chris Van Hollen, D-Md., said he was blocked Thursday from entering the El Salvador prison that is holding the Maryland resident who the courts say was erroneously deported from the United States last month.

The Maryland senator, who flew to the country on Wednesday, shared a video on social media showing guards stopping him and others from entering CECOT, where Kilmar Abrego Garcia is being held.

The Supreme Court and a Maryland federal judge ordered that the U.S. government “facilitate” Abrego Garcia’s return to the U.S. after the Department of Justice said in court filings that the 29-year-old father was wrongfully deported because of an “administrative error.” The Trump administration has alleged it cannot bring him back and claimed outside of court that Abrego Garcia is a member of the MS-13 gang.

Van Hollen was joined by Chris Newman, who he said is the attorney for Abrego Garcia’s wife and mother, and said they are trying to check on the deported man’s condition.

The video also showed Van Hollen and Newman speaking to prison guards, who were visibly shaking their heads “no.”

“These soldiers were ordered to prevent us from going any farther from this spot,” Van Hollen said. “I understand we’re about three kilometers now from CECOT, and as you can see, they’re letting other cars go by, but they stopped us because they’re under orders not to allow us to proceed to check on the well-being of Kilmar Abrego Garcia.”

Over the last couple of weeks, Republican members of Congress have gained access to the prison and posted pictures on their social media pages from inside the complex.