HELSINKI - One person was killed and three injured in a shooting at a school in a southern Finland on Wednesday, an official at the local authority said.

One of those shot was the head teacher of the school, said Tuula Panula, spokeswoman for the Tuusula municipality, some 60 km (40 miles) from the Finnish capital Helsinki.

"There is no information about the shooter. One of those who were shot at was the principal of the school," Panula said.

She said there were also injuries from glass debris.

Junior Constable Olli Laine said local police had surrounded the building, which houses both a middle school and high school, and were evacuating students.

Eero Hirvensalo, medical incident commander, said there were still people inside the building and that medical teams had been put on standby.

The Finnish News Agency said a teenage high school pupil opened fire in the middle of a class, but officials did not confirm this.

Violent incidents are rare at Finnish schools. The Finnish News Agency said there had been four stabbings at schools since 1999, but none of these caused fatalities.