Jamala, victor of last year's Eurovision Song Contest who took the crown for Ukraine, was joined on stage by an uninvited guest during her performance at this year's concert.
The singer maintained her composure and continued her song as security dragged him off the stage.
Celebrity pest Vitalii Sediuk is the man who invaded the song contest stage and bared his bottom.
The Ukrainian authorities did not see the amusing side, and have detained him for a period of 72 hours.
NZ cyber firms monitor global attack
It has had to cancel routine appointments and ambulances are being diverted to neighboring hospitals, Barts said. The National Cyber Security Centre said it had detected 188 "high-level" attacks in just three months.
A similar incident occurred at the 2010 competition in Norway when the Spanish entry had to perform for a second time following a stage disturbance. He could face anything from a fine to five years in prison on hooliganism charges, Mr Avakov said in a Facebook post.
Vitalii Sediuk is famous for his pranks as previous year he assaulted Kim Kardashian and Gigi Hadid during their visits in Paris.
Sedyuk had previously gained worldwide attention with stunts targeting the global entertainment elite, including trying to kiss actor Will Smith at a 2012 film premiere in Moscow and grabbing the microphone from British singer Adele as she accepted an award at the 2013 Grammy Awards.
I think we all owe Australia a gargantuan apology after last night's Eurovision Song Contest.