US President Joe Biden has implored Americans to “cool it down” following the attempted assassination of his rival Donald Trump on Saturday.
The right ear of presidential hopeful Mr Trump was pierced by a bullet in the shock shooting at a campaign rally in Pennsylvania.
Amid rising fears of political violence, Mr Biden delivered a prime-time televised address from the Oval Office in the White House on Sunday, warning politics must not be “a killing field”.
"There is no place in America for this kind of violence, for any violence ever. Period,” he said. “No exceptions. We can't allow this violence to be normalised.
“The political rhetoric in this country has gotten very heated. It's time to cool it down.
"We debate and disagree, we compare and contrast...but in America we resolve our differences at the ballot box," he added.
"Politics must never be a literal battlefield. God forbid a killing field."
Mr Biden and Mr Trump spoke to each other on Saturday night after the shooting. First Lady Jill Biden also spoke with former First Lady Melania Trump on Sunday afternoon, said a White House official.
Mr Trump and Mr Biden are locked in a close election rematch, according to most opinion polls including by Reuters/Ipsos. The shooting on Saturday shook up discussion around the presidential campaign, which had been focused on whether Mr Biden, 81, should drop out following a “historically bad” June 27 debate performance.
Mr Trump’s aides said the Republican candidate was in "great spirits" and doing well on Sunday evening. His presidential campaign is expected to resume again in earnest ahead of the upcoming Republican National Convention.
Former president Mr Trump arrived in Milwaukee on Sunday evening for the convention, which begins on Monday. He told the Washington Examiner that he had rewritten his speech for the event to focus more on national unity than on the policies of Mr Biden.
The gunman has been identified by the FBI as 20-year-old Thomas Matthew Crooks.
One person in the crowd was killed and two others critically wounded, before Secret Service agents fatally shot the suspect.
The agency said Crooks acted alone, but was yet to identify his motive.
Crooks was a registered Republican, according to state voter records, and donated $15 to a Democratic political action committee when he was 17.
He lived in Bethel Park, Pennsylvania, around 50 miles (80 kilometers) from the scene of the shooting.
He worked as a dietary aide at a nursing home, which said he "performed his job without concern and his background check was clean."
The gun - an AR-style-5.56 calibre rifle - had been bought legally, FBI officials said, adding they believed it had been purchased by Crooks’ father.
The officials said "a suspicious device" was found in the suspect's vehicle, which was inspected by bomb technicians and later rendered safe.
Law enforcement officials speaking under condition of anonymity told The Associated Press that bomb-making materials were also found at Crooks’ home.
Mr Biden has ordered an independent security review of the attack, which has prompted questions about how a gunman was able to open fire from a rooftop near the rally.
The FBI was investigating the shooting as a potential act of domestic terrorism.
In a post on Sunday on his social media site, Trump said: "In this moment, it is more important than ever that we stand United, and show our True Character as Americans, remaining Strong and Determined, and not allowing Evil to Win."
The rallygoer who was killed was Corey Comperatore, a former fire chief from the area, according to Pennsylvania Governor Josh Shapiro, who said Mr Comperatore "died a hero."
"His wife shared with me that he dove on his family to protect them," Mr Shapiro said. The two wounded bystanders were said to be in a stable condition.
