Damiano David, lead singer of Eurovision winners Maneskin, has categorically denied taking drugs during last night's grand final.
The rock band gave Italy their first win at the contest in more than 30 years, beating off competition from the likes of France, Switzerland and Italy to lift the trophy.
In a clip that has gone viral online, David is seen with his bandmates awaiting the results when he hunches down over their table - with some users claiming that it seemed as if he was snorting drugs.
Asked about the incident at a press conference afterwards, he replied: "Thomas (guitarist Thomas Raggi) broke a glass... I don't use drugs, please guys, do not say that.
"Don't say that really. No cocaine please, do not say that."
In a statement on Instagram on Sunday, the band said: "We are really shocked about what some people are saying Damiano doing drugs.
"We really are against drugs and we never used cocaine. We are ready to get tested, cause we have nothing to hide.
"We are here to play music and we are so happy about our Eurovision win and we wanna thank everyone for supporting us.
"Rock 'n Roll never dies. We love you."
A statement from the European Broadcasting Union issued on Sunday said: "We are aware of the speculation surrounding the video clip of the Italian winners of the Eurovision Song Contest in the Green Room last night.
"The band have strongly refuted the allegations of drug use and the singer in question will take a voluntary drug test after arriving home. This was requested by them last night but could not be immediately organized by the EBU.
"The band, their management and head of delegation have informed us that no drugs were present in the Green Room and explained that a glass was broken at their table and it was being cleared by the singer.
"The EBU can confirm broken glass was found after an on site check. We are still looking at footage carefully and will update with further information in due course."
Maneskin's triumph was Italy's third win in the contest and their first since their 14-year absence from the show.