British intelligence now believes the daughter of former Russian spy Sergei Skripal unwittingly brought the lethal nerve agent to the U.K. in her suitcase, which was used in his attempted murder. The Telegraph, citing senior British intelligence sources, reported a new theory that the novichok nerve agent was planted in Yulia Skripal’s suitcase before she left Moscow for London, making it much more difficult for the U.K. to trace who was specifically responsible for the attack. Both Yulia and Sergei Skripal remain in critical condition at a hospital following the attempted murders that took place nearly two weeks ago and sparked a furious diplomatic war between Russia and the West. The new theory proposes that an item in Yulia Skripal’s luggage—such as some clothing, cosmetics, or a gift intended for her father—was contaminated with the nerve agent with the intention that it would be opened in Sergei Skripal’s home in Salisbury, England. According to British police, Yulia Skripal flew to London from Russia on March 3.