AMSTERDAM — In a simple act of solidarity, same-sex couples and many others across the Netherlands have held hands this week to protest the beating of two gay men — an attack that shook a nation that has long prided itself on its tolerance.

The beating in the eastern city of Arnhem was far from isolated in the Netherlands, long seen as one of the world's most welcoming to same-sex couples. The city's mayor conducted the world's first gay marriages in 2001.

But it has touched a raw nerve in this nation whose tolerance on other fronts has eroded in recent years with the rise of anti-Islam and anti-immigrant populism and a crackdown on the country's famed liberal drug policies.

On Wednesday evening hundreds of people walked hand-in-hand through the streets of Amsterdam to express solidarity with the victims of the beating in the early hours of Sunday.

Moved to tears scrolling through the #allemannenhandinhand hashtag. Such a simple, beautiful display of support and solidarity. pic.twitter.com/HSzjdY9Fn2 — Raymond Braun (@raymondbraun) April 5, 2017

Police said the men told officers they were verbally abused by a group of youths because they were walking hand-in-hand over a bridge. In the confrontation that followed, both men were injured, and one had his front teeth smashed out.

"I find it really absurd, unbelievable, and this is feeling like we are going backwards," said Sjag Kozak, an Israeli who married his husband in Amsterdam and has lived in the freewheeling Dutch capital for 21 years. "So that's why we're here: To make a statement to let people know that we are moving forward and not going backwards."

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A well-known magazine publisher and journalist, Barbara Barend, triggered the action when she appealed on Twitter: "Can all men (hetero and homo) please just walk hand in hand this week ..."

That sparked the viral hashtag "allemannenhandinhand" (all men hand-in-hand,) with everybody from the Dutch deputy prime minister and finance minister to sports stars and TV personalities posting pictures of themselves holding hands.

Men of the #Netherlands embassy in #Athens holding hands to protest against violence against the #LGBT community #allemannenhandinhand pic.twitter.com/Nclss3h1cW — NL Embassy Greece (@NLinGreece) April 5, 2017

In one of the highest profile demonstrations of solidarity, two politicians involved in talks to form a new ruling coalition following last month's elections walked hand-in-hand across a square in Parliament.

"In the Netherlands we think that it's normal to be able to show who you are as a person, but apparently for some people it's not," said lawmaker Alexander Pechtold.

Dutch Prime Minister Mark Rutte weighed in, too, calling the Arnhem incident "terrible."

Five suspects, all in their teens, were to be charged Thursday with causing serious bodily harm, prosecutors said, adding that they are still investigating the motive of the attack.

Dutch gay rights organization COC says that 70 percent of gay, bisexual and transgender people in the Netherlands have suffered verbal or physical violence. The number of complaints filed with police has risen from 428 in 2009 to 1,574 in 2015, according to spokesman Philip Tijsma.

However Tijsma said it isn't clear if the number of attacks is on the rise or if victims are becoming more willing to report such violence to police.

"Dutch people are still tolerant," Tijsma said. "We are still worried about it, but it is not like you can't be safe on the streets of Amsterdam."

Barend, who helped start the campaign, called for a sustained change in attitudes.

"Once again, let's not leave it at this — politicians, police, everybody, let's make sure that really all men can go hand-in-hand along the street," she tweeted.

And while the campaign may have started in the Netherlands, it didn't end there. Here are some examples of its global reach:

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