Milwaukee, 16 July 2024 (dpa/MIA) - The US Republican Party officially nominated Donald Trump as its presidential candidate at its national party convention in Milwaukee, Wisconsin on Monday.

Trump received the necessary majority of delegates' votes at the party gathering, which began just two days after an attempt on his life that shocked the country.

A short while earlier, Trump announced that he had picked JD Vance, a 39-year-old senator from Ohio, to be his vice presidential running-mate.

"I have decided that the person best suited to assume the position of vice president of the United States is Senator JD Vance of the great state of Ohio," Trump wrote on his social media platform Truth Social.

Vance's memoir "Hillbilly Elegy" was a bestseller, and although he was once a scathing critic of Trump, he has since wholeheartedly embraced him.

If Trump wins the presidential elections in November, Vance would become one of the youngest vice presidents in US history.

Trump and Vance were the "most unifying and competitive ticket in political history," campaign advisors Chris LaCivita and Susie Wiles said in a statement.

"Donald J. Trump's record of success as a businessman and as a president who made America wealthy, safe, strong, and great again, coupled with J.D. Vance's inspirational biography, military service, and dedication to America's working families, will appeal to voters of all backgrounds across the country."

The Republican National Convention opened just two days after a shooting at a Trump campaign rally sent shockwaves through the US and plunged an already tumultuous campaign into dark territory ahead of the November 5 election.

The election is set to be a rematch between Trump and the incumbent Democratic President Joe Biden.

Vance was "a clone of Trump on the issues," Biden said according to journalists with the president. "I don't see any difference," Biden added.

Current Vice President Kamala Harris is set to be Biden's running-mate again. The Democratic ticket has however been thrown into some confusion by doubts about Biden's fitness for office.

The Democrats will meet for their convention in Chicago, Illinois, in mid-August.

Trump, who is the only president to have ever been impeached twice, has several criminal cases hanging over him.

High-profile Republicans and members of Trump's family are set to address the crowd over the four days of the convention.

Controversial topics that could alienate some moderate voters, such as abortion or the storming of the Capitol by Trump's supporters in January 2021, are set to be avoided at the convention, according to US media reports.

On Saturday, during a campaign event in Butler, Pennsylvania, a shooter was able to climb to an elevated position with an assault rifle and fire a number of shots at Trump, causing panic to break out in the audience.

Trump, wounded in the ear and left bleeding, struck a defiant tone as he pumped his fist while being whisked off the stage.

A firefighter watching the rally was killed and two others seriously injured.

"By luck or by God, many people are saying it’s by God, I'm still here," Trump told the New York Post. "I'm not supposed to be here. I'm supposed to be dead."

The perpetrator, killed by Secret Service agents, was 20-year-old Thomas Matthew Crooks from nearby Bethel Park, Pennsylvania. His motive for the shooting is not yet clear, investigators said.

In the wake of the assassination attempt, Biden instructed the Secret Service to review security measures for his Republican rival's convention.

US Department of Homeland Security secretary Alejandro Mayorkas said Biden had also directed the Secret Service to provide protection to independent presidential candidate Robert Kennedy Junior.

Kennedy is the son of former US Senator Robert Kennedy and nephew of former president John Kennedy, who were both assassinated in the 1960s.

Mayorkas said both Biden and Trump were "constantly" the subject of threats.

"We are in a heightened and very dynamic threat environment," he said.

"Maintaining the safety and security of the President, the former President, and their campaign events is one of our most vital priorities."