"Russian tanks have invaded Georgia and the country's president has been killed."

That is what Imedi TV, one of Georgia's most popular television channels, reported on Saturday night. It also broadcasted video of what appeared to be the Russian army in the country.

In reaction, many Georgian residents rushed into the streets in panic and emergency services were flooded with phone calls. Even a number of heart attacks were reported to have occurred.

But when the broadcast turned out to be untrue, widespread panic across the country turned into anger.

The pro-government channel later apologised, saying it was a mock newscast to show "what the worst day in Georgian history might look like". It also said it "should have clarified" that the programme was a fake TV report.

Relations between Russia and Georgia remain tense nearly two years after the 2008 war between the two countries, in which more than 200 Georgians died.

Al Jazeera's Matthew Collin reports from Tbilisi, the Georgian capital.