Amy Winehouse has been questioned by police in connection with a video which appeared to show her smoking crack cocaine.
Though the singer was not arrested, she was interviewed under caution in relation to the alleged unlawful possession of a controlled drug, a Scotland Yard spokesman confirmed.
The 24-year-old was admitted to a London rehabilitation clinic on January 24th, days after the Sun newspaper publicised a video which seemed to show Winehouse admitted to taking "six Valium" tablets before lighting up and inhaling from a crack pipe.
The newspaper claim the footage was part of a 19-minute drug binge at her east London home, in which the Back to Black star also took ecstasy and cocaine.
A statement issued by her record company Universal Music after the video was published said: "We are deeply disappointed and upset by these latest revelations and are doing everything we can to offer Amy our full support in dealing with her problems."
Winehouse temporarily left the Capio Nightingale rehabilitation facility this week so as to visit the US embassy in London in order to obtain a visa.
She is scheduled to perform at the Grammy Awards ceremony in Los Angeles this Sunday, at which she is nominated for six prizes.
At the time of her admission to rehab, her father Mitch told the Sun: "Your video of Amy taking drugs may well be the best thing that has ever happened to her.
"For all the hurt and pain, it may finally be the thing to focus her mind and convince her to get the help she needs to quit for good."