Many foreign websites were blocked Friday on mobile phones in central Moscow under restrictions that have gripped the Russian capital for more than a week, derailing the routine of millions of residents and slamming businesses that rely on cellphone internet. Russian authorities have said the restrictions are part of security measures to fend off Ukrainian drone attacks, but many industry experts suspect they are part of preparations by the authorities to block Russians' access to the global web if the Kremlin decides to do so. The intermittent shutdowns, which had previously been recorded in dozens of Russia's regions for months, have prompted some Moscow residents to turn to long-forgotten gadgets like walkie talkies, pagers and media players. The shutdowns are part of multipronged efforts by the authorities to rein in the internet. They have adopted restrictive laws and banned websites and platforms that don't comply. Technology also has been perfected to monitor and manipulate .