Amy Winehouse's mother-in-law has hit out at the troubled singer after she was allegedly caught on video taking cocaine - calling on police to arrest her.

Georgette Civil - whose jailed son Blake Fielder-Civil married Winehouse last year - reacted with anger after being shown a 36-second clip of the star appearing to snort the drug in a packed London pub last month.

She tells Newsoftheworld.co.uk, "I'm shocked by the video. When I look at Amy I think: 'For Christ's sake, just get a grip of yourself.'

"Enough is enough. As the police know Amy is a drug addict - and she has now been caught twice on film taking illegal drugs - they should arrest her and put her behind bars."

"Rehab clinics are a waste of money, unless you want them to work. Amy doesn't want to give up drugs, so she's got to learn the hard way in prison."

"Police have to act. She is making a mockery of the law. It has got to stop. The price Amy has got to pay is losing her freedom."

Winehouse is reportedly undergoing rehab treatment in a facility close to where Fielder-Civil is serving a prison sentence for actual bodily harm and perverting the course of justice.