After President Donald Trump cited a non-existent incident “last night in Sweden” during a rally on Saturday night, Twitter was quick to skewer him for the gaffe while speculating pointedly about what he might have meant.

“You look at what’s happening. We’ve got to keep our country safe,” Trump told a crowd in Melbourne, Florida. “You look at what’s happening in Germany. You look at what’s happening last night in Sweden. Sweden! Who would believe this? Sweden! They took in large numbers, they’re having problems like they never thought possible.”

Swedes on Twitter—and social media users at large—were baffled by Trump’s claim, as there was no incident in Sweden the night before his rally.

Former Swedish prime minister Carl Bildt wondered: “What has he been smoking?”

Trump, discussing terror, seamlessly mentions incident “last night in Sweden”. There was NO “incident” in Sweden last night. pic.twitter.com/XtcC4PRiNU — Steve Kopack (@SteveKopack) February 19, 2017

Literally the biggest incident of Sweden last night was a horse called Biscuit being rescued from a well. https://t.co/CAYsHhpt6z — Grapey (@Grapeykins) February 19, 2017

No. Nothing has happened here in Sweden. There has not ben any terrorist attacks here. At all. The main news right now is about Melfest. -> — @sweden / Emma (@sweden) February 19, 2017

turns out “what happened last night in Sweden” actually just means “last night I was watching Tucker Carlson talk about Sweden” pic.twitter.com/6z5pfOJ7Yv — Ashley Feinberg (@ashleyfeinberg) February 19, 2017

After the terrible events #lastnightinSweden , IKEA have sold out of this: pic.twitter.com/Bs1XI7ffKG — Jeanna Skinner (@JeannaLStars) February 19, 2017

What happened in Sweden Friday night? Did they catch the Bowling Green Massacre perpetrators? — Chelsea Clinton (@ChelseaClinton) February 19, 2017

Sweden? Terror attack? What has he been smoking? Questions abound. https://t.co/XWgw8Fz7tj — Carl Bildt (@carlbildt) February 19, 2017

The President’s comment was just the latest in a line of missteps by members of his administration who have cited non-existent attacks to defend his hardline positions on national security and immigration.

Top White House advisor Kellyanne Conway cited the non-existent “Bowling Green Massacre” earlier in February while defending Trump’s ban on visitors from seven predominantly Muslim countries.

Days later, White House press secretary Sean Spicer cleared up confusion about several previous references he made to a mysterious attack “in Atlanta.”

He said that he “clearly meant Orlando,” apparently referring to the gunman who killed 49 people at a gay nightclub in Orlando in June in the deadliest mass shooting in modern American history.