On Sunday morning, police received a notification that about 20 people had gathered on a public plaza in Leppävaara, Espoo, just west of Helsinki.
Police found the gathering at Läkkitori Square to be a religious public event, and suspended it for violating of restrictions on public gatherings. Police had not been notified of the event in advance.
After some time, police noted that public speaking was continuing and that people were still gathering at the site. The square is adjacent to the Galleria shopping centre, across the road from the Sello mall.
Police once again ordered the group to disperse and detained two people on suspicion of refusing to comply with police orders.
"The halting of the event went smoothly. Two people had to be taken into custody when orders were not followed. Force was not necessary," Detective Inspector Ilmari Hallamaa of the Western Uusimaa Police told Yle.
Based on a decision by the Regional State Administrative Agency for Southern Finland, public events with more than six people are prohibited until the end of April.
Commercial broadcaster MTV reports that the street worship service was organised by Espoon Kotikirkko (Espoo Home Church), which is part of the Finnish Baptist Church.
The group invited the public to join the event on its website, without any mention of coronavirus restrictions on group size.
Elsewhere on the site, the parish says that its events "allow the possibility of maintaining safety distances" and that "the decision to wear a mask is up to each person's own understanding and conscience" – but does not directly recommend either measure.
A day earlier, 20 people were detained in Helsinki for anti-restrictions protests that violated rules on public gatherings.