British police said documents seized from the partner of a journalist who has led coverage of Edward Snowden's leaks were "highly sensitive" and, if disclosed, could put lives at risk.
Counter-terrorism detectives said yesterday they had launched a criminal investigation following a preliminary examination of the material taken from David Miranda, partner of American journalist Glenn Greenwald, after he was held for nine hours at Heathrow Airport on Sunday.
Miranda, a Brazilian citizen who had been ferrying documents between Greenwald and a Berlin-based journalist contact of Snowden's, was held at Heathrow under anti-terrorism powers before being released without charge minus his laptop, phone, a computer hard drive and memory sticks.
"Initial examination of material seized has identified highly sensitive material, the disclosure of which could put lives at risk," London's Metropolitan Police said in a statement.
The police refused to give any further details about the criminal inquiry, and Miranda's lawyer, Gwendolen Morgan, said she knew very little about the investigation or its basis. Earlier, Miranda's lawyers went to London's High Court to try to prevent British authorities from looking at the tens of thousands of documents on the seized devices.
However, two judges gave the authorities until Friday to sift through the documents on condition it was done in the interest of national security and to investigate possible links to terrorism.
"We welcome the decision of the court, which allows our examination of the material … to continue in order to protect life and national security," the police statement said.