Prime Minister Sanna Marin (SDP) was no longer on summer holiday at the time she was filmed partying with friends, news agency STT reported on Friday, noting that this means no replacement had been appointed to take over her duties.
The video has sparked a heated debate about Marin's role and responsibilities as PM.
Commercial broadcaster MTV reported on Thursday that the party was likely to have taken place on Saturday 6 August while Seiska magazine wrote that Marin was also spotted in the Helsinki nightclub Teatteri that same Saturday night.
The Prime Minister had originally been due to take annual leave from Friday 5 August to Sunday 7 August that week, but this was subsequently cancelled.
Marin had returned to work from an extended four-week summer holiday on Thursday 4 August of the same week, according to information publicly available on the website of the Finnish government.
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