ISIS supporters have issued a chilling warning to the city of Moscow using a publicly available wifi network on the underground train system, according to Russian media.
The wifi network is available across the Moscow underground rail network and is named, "Paris was yesterday, Moscow is today".
When users successfully log-on to the network, they are presented with a jet-black ISIS flag and another warning about an imminent threat to the Russian capital city.
It is believed the public wifi network was renamed earlier this week, following a successful hack.
Train passengers alerted the authorities about the wifi network, which was spotted on the north-south Kaluzhsko-Rizhskaya line.
Local man Denis Savin, told Russian news website LifeNews: "I took my tablet and tried to connect to the WiFi but instead of the authorisation page I saw a black flag with an Arabic sign and words in Russian above it.
"It read: 'Paris was yesterday, Moscow is today'."
A screenshot of the ISIS-themed authorisation page was then sent to the police, the news site has reported.
The Russian Metro train network carries some 6.75 million people around the capital each day.
Metro wifi operator MaximaTelecom confirmed in a statement: "We have not registered any technical failures and there is no evidence that such a failure took place."
Like the Virgin Media wifi network available across the London Underground, Metro passengers must register before they can use the network.
The wifi network is available in trains and inside underground stations across Moscow.
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