Five days after the worst attack on New York since September 11, 2001, the city staged a show of defiance Sunday, with some 2.5 million people packing the streets to cheer on 50,000 marathon participants from around the world.

In a befitting finish, Shalane Flanagan, 36, became the first American in 40 years to win the women's title, overcoming a slow start to capture her first major world marathon crown in an unofficial time of 2 hours 26 minutes 53 seconds.

The men's title was taken by 24-year-old Geoffrey Kamworor of Kenya in an unofficial time of 2 hours 10 minutes 53 seconds.

Many who had come to watch spoke of overcoming their fears as New Yorkers proved their resilience in the aftermath of a truck attack that killed eight people and wounded 12 others in Manhattan near the 9/11 Memorial.

Dense crowds lined the route as the elite women began the race at 1420 GMT and the elite men followed half an hour later in cool and cloudy conditions.

Spectators rang bells and held banners, while bands played songs in an atmosphere more festive and louder than ever.

"They didn't win and we're here and we're going to have our marathon and we're going to cheer," said Leslie Mesnick-Uretsky, who ran the marathon in 2006.

"It's a lot of pride, not only for New York, but all the countries that came here."

The city heavily bolstered security for the race, parking massive sand trucks to prevent vehicle attacks, stationing extra police on rooftops and deploying more anti-sniper units.

Hundreds of uniformed officers stood along the route, while plainclothes officers blended in with the crowds of spectators.

President Donald Trump insisted in an interview that aired Sunday, as he began an extended Asia trip, that Americans should never accept terrorism as inevitable.

"We cannot just say, 'Oh well, it's going to happen, let's get used to it.' We cannot allow it to happen," he said on the Full Measure syndicated television show. "I can tell you, the Trump administration is getting tougher and tougher and tougher."

But awareness of the potential threat was a constant during the marathon. In iconic Central Park, where the race ended, a woman's amplified voice offered a repeated warning even before the race began: "Stay alert at all times."

- 'It did make me anxious' -

Security in New York had already been boosted in 2013 after the Boston marathon attack that saw two youths of Chechen descent plant two bombs near the finish line, killing three people and wounding more than 250 others, including spectators.

The Islamic State group has described Sayfullo Saipov -- the 29-year-old man charged with driving a rented pickup truck down a crowded bike path in Manhattan on Tuesday -- as one of its own, prompting Trump to call for his execution.

As the marathon began, New Yorkers said they were coming together in the aftermath of the latest attack to strike America's most populous city.

In the Bay Ridge neighborhood of Brooklyn, Jean Schnell was waiting to see her daughter run past. Tuesday's attack made her nervous, she admitted, especially because she is from Boston.

"It did make me anxious about coming to New York, and her running, but we were going to come support her anyway, so it didn't really make any difference," she said. "I think today you have to live your life."

But despite the attack, the drizzle that began to fall early on and cool temperatures, New York made its marathon a loud event filled with constant cheers and an incongruous mix of rap, rock, country, merengue and folk music.

"After 20 miles, it got rough, but the crowd support just kept me going," said Bill Bentley, who was running in the New York race for the first time.

- It 'helps people heal' -

Flanagan, the 2008 Olympic silver medalist in the 10,000-meter event, had earlier underscored that sort of determination.

"What I do know, 100 percent, is that we're a very resilient nation and I don't think there are many tougher people than New Yorkers, and marathoners are pretty tough too," she said before the race.

"So I think it's an opportunity to show resilience and strength and coming together... And when you come together as a community it really empowers people and helps people heal."

Flanagan said the carnage in New York had hit her hard as a veteran of the 2013 Boston marathon.

"It's obviously devastating and very concerning," she said of the New York attack.

"I've been in a terrorist attack in 2013 in Boston. I was there that day and had just completed my race. So it very much hits home and is very personal to me."

Flanagan said she would consider retiring if she stunned the field with a victory on Sunday.

Source: AFP