Vandals in Pirkanmaa set fire to a park bench that was painted in rainbow colours marking Pride Month, according to regional newspaper Aamulehti.
The bench, which was painted last week by a group of youths in the municipality of Lempäälä, was apparently doused with flammable liquid and then set ablaze.
The municipality's human resources chief, Auli Nevantie, called the incident regrettable.
"This has hit a nerve. This is also particularly unfortunate and even touching, because it was important for young people to take part in implementing, and conveying to others, the principles of equality," she said.
The municipality of Lempäälä is a an official supporter of Manse Pride Week, a six-day event organised by the City of Tampere and Sinuiksi, an NGO that advocates for equal human rights, regardless of sexual orientation, gender identity or gender expression.
On 10 June a local youth and cultural services group will hold a Pride picnic for young people along the Myllyranta shore, where the painted bench is located.
The week's events conclude on Saturday, 11 June with a Pride march.