"Following revelations that a UK spy agency unlawfully spied on PI, we have written to the Home Secretary asking him to instruct the agencies to provide a full explanation as to why they unlawfully held & analyzed our data," Privacy International said on Twitter, publishing a copy of the letter to Sajid Javid.
The charity also published documents proving that UK intelligence had spied on the organization.
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The statement comes after earlier in the day, UK's domestic intelligence service MI5 admitted in legal disclosures that it had obtained and read Privacy International's private data as part of its programs involving data harvesting. In a separate series of disclosures, MI5, as well as other UK intelligence agencies — Government Communications Headquarters (GCHQ) and MI6 — also revealed they had collected data about Privacy International or its staff.