HELSINKI, Finland (AP) _ Reports of a lion roaming in southeastern Finland were considered a summer joke until last weekend, when police issued a warning against visiting forests in the area.

A lion was spotted on June 23 by a forester near the village of Ruokolahti, 170 miles northeast of Helsinki, police said Sunday.

''He was worried about telling us about it as he couldn't believe his eyes,'' said Police Chief Commissioner Urho Parikka. ''He thought nobody would take him seriously.

''There's no reason for panic as it seems the lion wants to avoid people. It's got plenty of game to eat in the forests,'' Parikka said.

According to unconfirmed reports, several circus animals escaped from an overturned Russian circus truck on a road between St. Petersburg and Vyborg, 20 miles from the Finnish border.