Ukraine introduced emergency power cuts in six regions amid what authorities described as a "massive" Russian missile strike, the national grid operator said on Wednesday.

The barrage appeared to be one of the largest recent assaults in Ukraine’s campaign to damage Russia’s war machine on its home territory.

Ukraine used six British Storm Shadow missiles and US-made Atacms tactical ballistic missiles in what Kyiv described as its “largest attack” on Russian military facilities.

Ukrainian forces used missiles and drones on Tuesday to target sensitive military and energy sites across Russia.

Moscow said on Tuesday that Ukraine had fired six U.S.-made ATACMS ballistic missiles, six UK-made Storm Shadow cruise missiles and at least 146 drones into Russia in an attack that it said would not go unanswered.

An air-raid warning has been issued across Ukraine on the morning of 15 January due to the threat of missile strikes. Source: map of air-raid warnings; Ukraine's Air Force; monitoring Telegram channels Details: An air-raid warning was issued in all Ukrainian oblasts due to the threat of a missile strike.