A member of the international computer hacking group Anonymous pleaded guilty in court in Britain on Saturday to breaking into and defacing the website of an abortion service.
James Jeffery, 27, said he targeted the site because he disagreed with his sister's decision to terminate her pregnancy, Westminster Magistrates Court in central London heard.
He stole around 10,000 records with the details of women who had registered with the site, and replaced the logo of the British Pregnancy Advisory Service with the Anonymous symbol.
Jeffrey then boasted about the attack on Twitter, using the alias "Pablo Escobar" after the Colombian drug lord who died in 1993 and printing the name and log-on details of a BPAS administrator.
Police arrested him on Friday at his home in Wednesbury, central England, after the abortion service raised the alarm.
Jeffrey admitted one charge of gaining unauthorised access to data and another of gaining unauthorised access to a computer with the intention of impairing its operation.
Judge Daphne Wickham described him as a "zealot with an anti-abortion campaign".
She refused to grant him bail, saying that he was an "able hacker" who could target other organisations and ordering that he should be held in custody until sentencing at a later date.
On Tuesday two Britons with alleged ties to Anonymous were among five people charged in the United States in in high-profile cyberattacks after a leader of the group became an FBI informant.
Ryan Ackroyd, 23, of Doncaster, and Jake Davis, 29, of Lerwick, Shetland Islands, were both arrested last year in Britain.
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