A man wielding a chainsaw in northern Switzerland has injured several people, police have told CNN, in what they said was an ongoing situation.

The incident happened in the historic town of Schaffhausen near the country's northern border with Germany.

Police did not give any further details.

Images of the scene on social media show a cobble-stoned street cordoned off, with police vehicles and ambulances in the area.

A journalist in Schaffhausen, Marco Latzer, told CNN that the incident occurred at around 11:30 a.m. (5:30 a.m. ET) local time and that he understood the perpetrator was "still on the run."

He said that the incident was a shock to the people of Schaffhausen.

"It's a very peaceful place ... a quiet place normally," he said.

"It's kind of a big thing for this town of course and many people here are really shocked."

This is a developing story.