Singer Amy Winehouse has been questioned in connection with a video which allegedly showed her smoking crack cocaine, a police source said on Wednesday.
A Scotland Yard spokesman said officers interviewed the 24-year-old in connection with an allegation of unlawful possession of a controlled drug.
He said she was not arrested, but was interviewed under caution and inquiries were continuing.
Last month footage obtained by the Sun newspaper appeared to show Winehouse inhaling fumes from a crack pipe.
The disturbing images were said to have been filmed during a party at Winehouse's London home.
The singer is now in rehab, admitting herself to the clinic in north London on 24 January days after the video appeared.
On 4 February the singer took a break from her treatment to apply for a US visa so she could attend the Grammys in Los Angeles on 10 February, where she is nominated for six awards.
The application process will not be simple due to her drugs record. Last October she was arrested and fined in Norway for possession of cannabis.
