A man has spent more than 24 hours perched halfway up a 321-foot radio tower in Washington DC in what appears to be a mental health crisis.

As reported by The Washington Post yesterday, the man climbed the tower at American University, on the 4400 block of Massachusetts Ave, NW, on Tuesday afternoon and was still there late Wednesday.

The unidentified man was refusing to come down, noted the report, which stated he's experiencing a mental health crisis and has threatened to jump.

DC Police have been attempting to talk him down from the tower, owned by radio station WAMU-FM.

Police first received reports that a man had climbed the tower just after 3pm on Tuesday (June 10). Since then, members of the police emergency response team have remained at the scene.

He appeared to be pacing on a platform roughly halfway up the tower, wearing a red hoodie and a backpack, reported the Washington Post.

WAMU's radio signal was briefly impacted on Tuesday afternoon, while WAMU stated they had “powered down the tower to support the emergency response.”

In the immediate aftermath of the incident, some buildings on the south side of the university campus were evacuated or put under a shelter-in-place order on Tuesday night.

In a letter to the university’s community Wednesday morning, Vice President Bronté Burleigh-Jones notified students to let them know that campus operations would resume as usual.

"In [the police] assessment, the individual does not pose a risk to the community or campus safety,” wrote Burleigh-Jones.

Update: As of Thursday, June 12, the man is still on the tower and refusing to come down, say police. He has been on the radio tower for more than 50 hours.

This is a developing story that we'll update as we find out more

If you are struggling with mental health, you can call the National Suicide Prevention Helpline UK on 0800 689 5652 or Samaritans on 116 123. In the US, The 998 Suicide & Crisis Lifeline can be reached by dialing 998.