Two United Nations groups say the number of migrants crossing the dangerous Darien Gap between Colombia and Panama could soar to as many as 400,000 this year.
That would represent a huge increase from the 250,000 estimated to have crossed the roadless, jungle-clad route last year.
The UN agencies for refugees and migration said in a report that nearly 100,000 people may have already made the crossing so far this year, six times more than in a similar period last year.
If that trend continues, it could mean many more migrants seeking to reach the United States through Central America and Mexico.