After last week's referendum on a "Brexit," a wave of racist incidents have been reported to British police and documented in widely shared social media posts. Since the referendum, the hashtag #Postrefracism has been trending, and its contents provide a disheartening view of how Britain's vote to leave the European Union may be emboldening those who harbor virulent racist sentiments.

A Facebook group called "Worrying Signs" now has more than 11,000 followers, many of whom are posting live updates from the scenes of such incidents. The group describes itself as "a space where you can share information, post pictures, add screen grabs (etc.) of any worrying signs or incidents of racism/xenophobia you've come across since the UK EU referendum results."

Some 800,000 Poles live in the U.K. but after their cultural center in London was vandalized, during a spate of hate crimes in recent days, many are wondering if the post-Brexit era means they are no longer welcome. (Reuters)

Tuesday morning, at least two young men harassed another man whom they perceived to be an outsider on a Metrolink train in Manchester. The incident, which was confirmed by police, was caught on video, which has now been widely shared.

Despite it being early in the morning, the young men appear to be drunk, and one flings beer onto the victim before leaving the bus. Fellow passengers prevent a fight from breaking out and then shout the young men down, calling them a "disgrace to Britain."

On Monday afternoon in Walsall, outside Birmingham, a man working at a halal butcher shop was injured after he was hit with a lit bottle containing flammable liquid. The shop was badly damaged, according to the BBC.

Police in West London were investigating what they called a "racially motivated" attack against the Polish Social and Cultural Association. Poles make up the largest foreign-born population in the United Kingdom. The organization's building was apparently defaced with graffiti that said, "Go home."

In Cambridgeshire, leaflets were apparently distributed with “Leave the EU/No more Polish vermin” written in both English and Polish. The Polish Embassy in London has expressed its "grave concern."

In a speech given to Parliament on Monday, Prime Minister David Cameron called the increase in hate crime "despicable." Some reports indicate that incidents have risen by over 50 percent since the referendum.

"In the past few days, we have seen despicable graffiti daubed on a Polish community center, we’ve seen verbal abuse hurled against individuals because they are members of ethnic minorities," Cameron said. "Let’s remember these people have come here and made a wonderful contribution to our country. We will not stand for hate crime or these kinds of attacks, they must be stamped out."

In a stunning victory for the "Leave" campaign, Britain has voted to exit the European Union. Here's what happens next. (Jason Aldag, Adam Taylor/The Washington Post)

Those campaigning for a Brexit offered clear assurances that a new immigration system would not affect E.U. citizens already living in Britain: “There will be no change for EU citizens already lawfully resident in the UK,” the campaign noted on its website. But despite the assurances, many immigrants to Britain are unsure of their future.

Racism isn't exactly an unexpected outcome of the victory for the Brexit camp at the polls, either. Nigel Farage, the leader of the U.K. Independence Party (UKIP) and the most hard-line proponent of a Brexit, has spoken of the "n----- vote" and told reporters that he would use a racist slang term to refer to Chinese restaurants. But he and other "Brexiteers" have said that their concerns are about increasing immigration flows perceived as coming at the expense of the British-born and have nothing to do with prejudice.

Britain's massively popular tabloids have done little to calm the public's nerves over immigration, often resorting to blatant scaremongering and race-baiting. Below is a compilation of dozens of tabloid fronts doing so.

The message of most of the attacks that have been reported since Friday seems to be simple: A victory for the Brexit camp should herald the repatriation of all non-white, non-Anglo-Saxons in the U.K. Never mind that the official campaign pushing for a Brexit expressly eschewed that sentiment.

What follows is a harrowing sampling of Twitter posts detailing specific incidents.

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