Switzerland's Nicole Brandli, who won silver in the time trial earlier this week, finished second with Spain's Joane Somarriba Arrola in third.

The victory caps an impressive season for the 26-year-old Swede.

"I really can't believe it, it's like a dream," Ljungskog said.

The four riders exchanged the lead throughout the final lap, keeping a close eye on each other in difficult conditions made worse by rain.

The slick road surface caused several crashes, including one that scuppered Welsh star Nicole Cooke's chances of victory.

Dutch star Leontien Zijlaard-Van Moorsel, Olympic champion and pre-race favourite, finished a disappointing 21st.

The 114-strong pack averaged speeds of around 43kph during the race at Zolder - the flattest course for a world championship in years.

In the final straight Ljungskog, a noted sprinter who won the final time trial of this year's Tour de France, was practically unchallenged as she coasted over the line.

"The front group had a good breakaway on with one lap to go so it was up to my team to chase them down," said Ljungskog, who admitted she did not even like the course.

"When we got to the last climb I heard a crash behind me and that's when I decided to go.

"I didn't actually like the course too much - I prefer hills and mountains - but I have strong legs so it doesn't matter what kind of course it is."

Second-placed Brandli said: "I'm very happy to have won two medals this week, although I would have preferred one of them to be gold - but maybe next time."