Clinton v Trump: Five key moments from the first debate
Donald Trump and Hillary Clinton have clashed in a fiery first presidential debate in the race for the White House.
The Democrat and Republican rivals squared off in a 90-minute debate at Hofstra University in New York, which was screened to tens of millions of television viewers in America and live-streamed around the world.
The rival candidates sparred on issues ranging from the economy and the fight against so-called Islamic State (IS) to their fitness for office and the "birther" controversy.
Here are five key moments from the debate.
Jobs and the economy
The first question dealt with Americans' wealth and work, with the two candidates taking different approaches.
Mr Trump attacked the Democrats' record in government, saying the US had lost jobs to the likes of China and Mexico before promising to revive the economy by lowering taxes, cutting regulation and renegotiating trade deals.
He repeatedly attacked his rival's husband, former US President Bill Clinton, for the North American Free Trade Agreement that was approved under his administration in the 1990s, saying it was the "single worst deal ever approved".
Read Robert Moore's blog: Did 'unprepared' Trump just lose his bid for presidency?
Mr Trump said: "We have to do a much better job at keeping our jobs. We have to do a much better job at giving companies incentives to build new companies expand.
"Hillary I'll ask you this - you've been doing this for 30 years, why are you just starting to think of solutions now? I will bring back jobs. You can't bring back jobs".
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In reply, Mrs Clinton said: "I have thought about this. When I was in the Senate, I had a number of trade deals come before me and I gave them the same test. New jobs with rising incomes."
She described her opponent's proposals to cut taxes for higher earners as "Trumped-up trickle-down" and pledged to achieve gender parity in the workplace and increase taxes for the wealthy.
Terrorism and security
Both candidates have faced questions during the campaign about how they would deal with the threat of IS, and Mr Trump was quick to bring national security into the debate.
The Republican candidate said the group were "beating us at our own game" on the internet and said America was "not doing the job we should be doing" on cyber security.
He accused Mrs Clinton of leaking tactics to IS on her campaign website and criticised Barack Obama's administration for the ascendancy of the terror group.
"You're telling the enemy everything you want to do. No wonder you've been fighting Isis your entire life," he said.
In response, Mrs Clinton said her rival had "consistently insulted Muslims abroad, Muslims at home", while people from within the Muslim community would be key to fighting terror.
The Democratic candidate said she is hopeful IS will be eradicated by the end of the year - with taking out its leaders her top priority in office.
Mrs Clinton said Mr Trump was too easily provoked to serve as commander in chief and could be quickly drawn into a war involving nuclear weapons.
"A man who can be provoked by a tweet should not have his fingers anywhere near the nuclear codes," she said.
Mr Trump said he "would strike first" in any nuclear exchange but added that he "can't take anything off the table" and referred to issues with Iran and North Korea.
Emails and tax returns
Both candidates have gone after the other on these issues in the run-up to the debate, and they did not disappoint on the night.
The Republican insisted he would publish his tax returns "against his lawyers' advice" if Mrs Clinton releases the 33,000 deleted emails from her private server.
His comments prompted cheers from sections of the audience, with moderator Lester Holt having to remind those watching to remain quiet.
Mrs Clinton said her use of a private email server was a "mistake" and claimed Mr Trump could be refusing to release his tax returns because he was not as rich or as charitable as he claimed.
She said: "I think probably he's not that enthusiastic having the rest of our country see what the real reasons are because it must be something really important, even terrible, he's trying to hide."
Race
Mrs Clinton accused Mr Trump of racism, saying he started his political career with a "racist lie" after he falsely suggested President Obama was born outside of America.
"He has a long record of engaging in racist behaviour," she said.
The candidates were asked how they would heal race relations in the wake of police shootings that have provoked outrage across the US.
Mrs Clinton said gun violence is the leading cause of death among young African-American men and tackling the "plague of gun violence" is critical.
She said: "Race remains a significant challenge in our country. Unfortunately race still determines too much - where you live, what education you can get, and yes, how you get treated in the criminal justice system.
"We have to bring communities together as a mutual goal. We have to have to tackle the plague of gun violence."
Mr Trump said many of those involved in gun violence were "illegal immigrants".
He added: "We need law and order. When I look at what's going on... in various parts of our country. We need law and order.
"African Americans and Hispanics are living in hell. In Chicago they've had thousands of shootings. Is this a war-torn country? You walk down the street you get shot.
"We have to bring back law and order. We have gangs - illegal immigrants - who are roaming the streets."
The pair clashed on "stop and frisk" laws, with Mr Trump claiming a judge's ruling that the practice was unconstitutional was wrong.
Fitness to serve
The health of the candidates has been under the spotlight in recent weeks, in particular since Mrs Clinton, 68, revealed earlier this month she had been diagnosed with pneumonia.
Mr Trump questioned whether she had the stamina to be president, saying: "You have so many different things you have to be able to do and I don't believe Hillary has the stamina." Mr Trump also claimed he had a "better temperament" than Mrs Clinton.
She said Mr Trump should not talk about stamina until he has tried out the busy schedule she kept up as secretary of state.
Both candidates appeared fit and well during the debate - however sniffling by Mr Trump set chins wagging on Twitter.
So who won?
It depends on whose side you listen to.
Following the debate, Mr Trump said Mrs Clinton had "failed", while his daughter, Ivanka Trump, told ITV News she thought her father's performance on the night was "incredible".
Congressman Peter King has told ITV News Mr Trump "took some of Mrs Clinton's supporters away from her", while American boxing promoter Don King said Mr Trump "didn't get a knockout".
Congressman Gregory Meeks claimed Mrs Clinton was "far superior to Trump", while her communication director, Jennifer Palmieri, told ITV News she thought Mr Trump "would be more disciplined".
ITV News Washington Correspondent Robert Moore said Mrs Clinton would be "delighted and relieved" with her performance, while Mr Trump "lost the narrative utterly".
What happens next?
Mr Trump and Mrs Clinton will take part in two more debates before the November 8 election.
Their running mates, Tim Kaine and Mike Pence, will square off next week