Swedes have been scratching their heads and ridiculing President Donald Trump's remark that suggested a major incident had happened in Sweden.

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.

The comment has prompted a barrage of social media reaction on Sunday.

Former Swedish Foreign Minister Carl Bildt tweeted , "Sweden? Terror attack? What has he been smoking? Questions abound."

Aftonbladet newspaper listed in English some events that had happened pn Friday in Sweden, including a man being treated for severe burns, an avalanche warning and police chasing a drunken driver.

One Twitter user posted a mock Ikea instruction manual on how to build a "Border Wall," saying the pieces had sold out.