Mobile internet access has been disabled in Moscow in recent days after similar outages in dozens of regions.

Moscow has said the measures are to protect against Ukrainian drone attacks, which can rely on cellphone towers. Hector Retamal/Agence France-Presse/Getty

Russia is stepping up its tests of systems designed to keep millions of people from accessing information online in times of political unrest, shutting off mobile internet access in the capital in recent days.

People in Moscow, a city of 13 million, have found themselves unable to pay online bills or message co-workers in recent days. Commuters stepping out of the city’s subway stations can’t order a cab to the office. Unable to access online maps.