Russia and Canada appear to be at war — on Twitter.

On Wednesday, after Ukraine accused Russia of sending soldiers across the Ukrainian border as part of a stealth invasion, Canada sent a message to Russia on Twitter.

“Geography can be tough. Here’s a guide for Russian soldiers who keep getting lost & ‘accidentally’ entering #Ukraine,” the official Canada at NATO Twitter account wrote.

The Tweet, retweeted nearly 30,000 times, included a map showing what is “Russia” and what is “not Russia.”

On Thursday, Russia responded.

The country attached a map showing Crimea as Russian territory, in an effort to help their “Canadian colleagues to catch up with contemporary geography.”

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