Updated at 1.13pm

US President Donald Trump left a baseball game early on Sunday after the crowd booed him and chanted “lock him up”.

Boos and jeers rang out across the stadium during Game 5 of the World Series between the Houston Astros and Washington Nations when Trump appeared on the big screen.

The audience cheered as the stadium carried a salute to US armed forces, hours after Trump had announced that Isis chief Abu Bakr al-Baghdadi had been killed “whimpering and crying and screaming”.

But those cheers quickly turned to loud boos when the stadium screens cut to the president and first lady Melania Trump.

In parts of the stadium, the crowd chanted “lock him up”, parodying a line which Trump’s own base used during the 2016 election to attack Trump’s rival Hillary Clinton.

Trump and his entourage left the stadium around 90 minutes before the game ended.

Demonstrators sitting behind the home plate also unfurled "veterans for impeachment" banners during the game, in reference to the House of Representatives investigation into whether Trump abused power by withholding military aid to Ukraine.

Trump has been on the back foot for weeks as the Democrats push ahead with their impeachment inquiries, and as he faces widespread and bipartisan condemnation of his Syria policy.

It was an unusual excursion for the president and first lady -- who arrived earlier at the Nationals Stadium, and sat in a suite behind home plate -- in liberal-majority Washington.

Prior to the Nationals-Astros showdown, Washington manager Dave Martinez said he hoped Trump "enjoys the game."

When asked if the team was excited for his arrival, Martinez replied, "We haven't really talked about it. We're focused on playing baseball."

The ceremonial first pitch was thrown out by Spanish-American celebrity chef Jose Andres, a vocal critic of Trump's controversial immigration policies and Puerto Rico hurricane relief efforts.