A man who set himself ablaze outside the New York City court where former US president Donald Trump is standing trial has died of his injuries, police said on early Saturday.

Police had previously identified the man as Maxwell Azzarello from St. Augustine, Florida.

Witnesses described seeing him throw pamphlets into the air on Friday just before dousing himself with an unspecified liquid and setting himself on fire in a park near the courthouse.

The man was rushed to treatment, but a spokesman for the New York Police Department confirmed to AFP early Saturday that the man had died, without offering further details.

Hearings in the Trump case resumed after lunch despite the incident. Trump declined to respond to questions about Azzarello as he returned to court after the break.