BBC News has confirmed that Cherif and Said Kouachi, the main suspects in Wednesday's attack on the Charlie Hebdo office, were on the U.K. Warnings Index.
An unnamed source told BBC News reporter Daniel Sandford that Cherif and Said Kouachi had been on the index "for some time." According to The Telegraph, the index is the U.K.'s "single most important electronic check" against suspected terrorists and criminals.
The pair were also on "no fly" lists in both Britain and the United States.