During a rally in Florida on Saturday, Trump said "look what's happening last night in Sweden" as he alluded to past terror attacks in Europe. It wasn't clear what he was referring to and there were no high-profile situations reported in Sweden on Friday night.
The comment prompted a barrage of social media reaction on Sunday, with hundreds of tweets, and a local newspaper published a list of events that happened on Friday that appeared to have no connections to any terror-like activity.
Foreign Ministry spokeswoman Catarina Axelsson said that the government wasn't aware of any "terror-linked major incidents." Sweden's Security Police said it had no reason to change the terror threat level.
"Nothing has occurred which would cause us to raise that level," agency spokesman Karl Melin said.
Axelsson told The Associated Press that the Swedish Embassy in Washington contacted the State Department on Sunday to request clarification of Trump's remarks and was waiting for an answer.
Former Swedish Foreign Minister Carl Bildt tweeted , "Sweden? Terror attack? What has he been smoking? Questions abound."
Addressing Trump in an article on Sunday, the Aftonbladet tabloid wrote, "This happened in Sweden Friday night, Mr President," and then listed in English some events that included a man being treated for severe burns, an avalanche warning and police chasing a drunken driver.
One Twitter user said, "After the terrible events #lastnightinSweden, IKEA have sold out of this" and posted a mock Ikea instruction manual on how to build a "Border Wall."
Sweden, which has a long reputation for welcoming refugees and migrants, had a record 163,000 asylum applications in 2015. The country has since cut back on the number it annually accepts.
Its most recent attack linked to extremism happened in the capital, Stockholm, in December 2010. An Iraqi-born Swede detonated two explosive devices, including one that killed him but no one else.
At the rally, Trump told his followers to look at what was happening in Germany, where a truck attack at a Berlin Christmas market killed 12 people. He also mentioned Paris, Brussels and Nice, in apparent reference to the terror attacks there.
The president didn't specify what was supposed to have happened in Sweden, simply saying "Sweden, who would believe this, Sweden."
Over the past few weeks, Trump counselor Kellyanne Conway has also referred to a "Bowling Green Massacre" that never occurred, and she was caught up in a public feud with CNN.
Former foreign minister Bildt told Swedish Radio after his initial confounded tweet Sunday that he sees danger in how Trump relates to facts.
"If we are in a situation where there is tension in the world, we stand between war and peace," he said. "If we then have a president who spreads lots of false rumors, it can be truly dangerous."
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