(CNN)Three teenage British girls suspected of traveling from London to Turkey with the goal of joining ISIS are now believed to have made it to their target country -- war-torn Syria -- London's Metropolitan Police said Tuesday. Police didn't elaborate, other than to say in a statement that they "now have reason to believe that (the girls) are no longer in Turkey" and have crossed into neighboring Syria, parts of which have been taken over by the Islamist terror group. If true, that would unsuccessfully end British and Turkish authorities' efforts to find the teens in Turkey before they could cross the Turkish-Syrian border.
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London's Metropolitan Police say they have reason to believe girls aren't in Turkey
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Family of woman who went to Syria in 2013 says security services have questions to answer
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Turkish official calls it "shameful" the teenage girls flew from London to Istanbul, Turkey
"And the real concern that arises is that if a known member of ISIS who's now a poster girl for @placeholder, seen to be recruiting and spreading propaganda, is in touch with young people in our country -- that one would expect the courtesy of a knock on the door of these families, to advise them that their children may be on the cusp of radicalization or going off to Syria."
But with the rise of the ultra-violent Islamist group ISIS in Syria, the @placeholder government increasingly came under criticism at home and abroad for not doing enough to stop jihadists from going through Turkey to get into Syria.