Watch: Biden travels to meet families of police killed in Charlotte shootout

Watch as Joe Biden travelled on Thursday (2 May) to meet families of police who were killed in the shoot-out in Charlotte, North Carolina, on Monday.

Four officers - Sam Poloche and William Elliott of the North Carolina Department of Adult Corrections, Charlotte-Mecklenburg officer Joshua Eyer, and deputy US marshal Thomas Weeks - died when a wanted man opened fire on them as they approached his home on 29 April 29 trying to serve him warrants.

Terry Clark Hughes Jr, 39, was wanted for possession of a firearm by a felon and felony flee to elude.

An AR-15 rifle and a 40-calibre handgun were found in the home, along with two other individuals whose relationship to Hughes was not immediately clear.

The pair haven’t been charged with a crime nor are they considered suspects.

Authorities said they have not ruled out the possibility “that someone else was firing as well.”

New details have revealed that Hughes, who was fatally shot during the exchange, led officers on a high-speed chase in January, according to Lincoln County Sheriff Bill Beam.

One of his officers tried to pull over Hughes but he "took off" rather than slowing down, the sheriff told WCNC.