Binanc.US has temporarily suspended USD withdrawals and deposits at 5:02 p.m. UTC as well as cryptocurrency purchases on its platform: 

USD withdrawals and deposits as well as ACH/Debit purchases are suspended temporarily for maintenance.” 

Prior to that, Binance, the largest cryptocurrency exchange in the world by reported trading volume, is currently experiencing “temporary difficulties,” according to its most recent Twitter announcement.    

UPDATE: Binance CEO Changpeng Zhao informed his followers that the issue was caused by a very high amount of traffic:   

“Should be back to normal now. Still very high load.”

The is a developing story. Stay tuned for updates.