Belarus' state-run BelTA news agency reported that a Ukrainian S-300 missile had fallen onto the territory of Belarus on Thursday during one of Russia's largest missile attacks against Ukraine since the start of the war.

The Minsk defence ministry was investigating whether Belarus' air defence systems had shot down the rocket or it was a misfire.

The incident occurred between 10 and 11 a.m. (0700-0800 GMT) - around the time Russia was firing scores of missiles towards Ukraine.

BelTA said the missile that landed in Belarus had come from Ukrainian territory. It published a photo of what it said were parts of a S-300 missile lying in an empty agricultural field.

BelTA said there was no information about casualties.

The S-300 is a Soviet-era air defence missile that is used by both Russia and Ukraine. In November, an S-300 believed to have been fired by Ukrainian air defences landed in Poland.

Kyiv has used the system to intercept incoming Russian missiles, while Russia has appeared to use repurposed S-300 missiles to attack ground targets - something that military analysts say could be a sign that its missile stocks are dwindling.

Belarus allowed Moscow to use its territory as a launchpad for the invasion of Ukraine in February, but has insisted that it is not participating in the war, and will not participate. (Reuters)