Was there a terrorist attack in Sweden Friday night? No, but U.S. President Donald Trump seemed to suggest there had been, leaving Swedes baffled by just what the new American leader might have meant by an offhand remark.

At a campaign rally Saturday in Florida, Trump alluded to past terrorist attacks in Europe linked to open-borders immigration, saying, “You look at what’s happening in Germany. You look at what’s happening last night in Sweden. Sweden. Who would believe this? Sweden.”

But there were no high-profile, terror-linked events in the Scandinavian country Friday night.

Trump did not elaborate on the remark until Sunday evening, when he tweeted that he was referring to a Fox News broadcast about migrants and Sweden.

In the meantime, some Swedes mocked Trump on social media accounts using the hashtag “#LastNightinSweden.”

Former Swedish Foreign Minister Carl Bildt took to Twitter, saying, “Sweden? Terror attack? What has he been smoking? Questions abound.” Some Swedes joked that Trump might have been referring to a large meatball theft, an avalanche warning or police chasing a drunken driver.

Another Twitter user, tweaking Trump’s plans to build a border wall on the U.S. southern border with Mexico to thwart illegal immigration, said that “after the terrible events” of Friday night, the giant Swedish retailer Ikea had sold out of instruction manuals on how to build border walls.

Gunnar Hokmark, a Swedish member of the European Parliament, retweeted a post that said, “#lastnightinSweden my son dropped his hotdog in the campfire. So sad!”

The Swedish embassy in Washington had asked the U.S. State Department for clarification on just what Trump was referring to.