The pictures show an increase in tents designed to accommodate troops at a number of Russian bases.

Previous satellite images have shown that Russia has been deploying large equipment, such as military vehicles, to their bases.

Those photos did not show that extra troops were also being sent to camps near or within Ukraine's border, or that these camps were even being prepared to receive extra soldiers. This includes bases in the Crimea Peninsula, an area illegally annexed by Russia in 2014.

The images released today are the first of their kind to show this.

A spokesperson for Maxar, who made the images available, said: "Over the past couple of months, military equipment/units have been deployed at or near a number of garrisons and to existing military training areas within Russia and Crimea and adjacent to the border with Ukraine."

He added: "Troop tents and shelters for personnel have been seen at virtually every deployment location in Belarus, Crimea and western Russia, which suggests that the units are now accompanied by troops and have increased their overall readiness level."

Images show recent deployments at camps in Crimea, Western Russia and Belarus.

The set of images focused on here were taken on 1 February and show a Russian camp in Novoozerne, a settlement in the Crimea Peninsula.

It is around 80 miles from the peninsula's boundary with government-controlled Ukraine.

Rows of tents can be seen filling up the large area at the bottom of the photo of the camp.

That same area is empty in an image of the base taken by Maxar on 15 September 2021 - and you can see the direct comparison below:

The presence of tents suggests that more troops than can be ordinarily accommodated at the base are gathering.

In both images, tanks and other military equipment can be seen at the top of the photo of the camp.

That equipment can be seen in greater detail in this image taken on 1 February:

Russian training exercises have been happening in Crimea but an analyst from global intelligence company Janes told Sky News that the tents at Novoozerne are unlikely to be linked to these drills.

He said: "The deployment of tents does not necessarily tie into training exercises. The location of this camp is pretty far away from the official training grounds in Crimea for one.

"It is relevant because this site houses equipment belonging to units which were deployed to Crimea from the Caucasus area during the Spring 2021 build-up. This equipment has remained at the site with relatively little activity until now."

Russian troop movements have been captured by satellite images before, but at bases far from the border.

The photos taken last year captured a Russian camp in Yelnya, a town some 200 miles from Ukraine.

Some of the images showed snow had melted from the tops of some of the tents. This indicated the tents were warm and so were likely to be in use by troops at the time the photos were taken.

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The bases in Crimea that Maxar have published photos of are in Novoozernoye, Bakhchysarai, Yevpatoria and the Opuk and Angarsky training areas.

In Western Russia, the bases are in Yelnya, Klintsy, Klimovo, the Kursk area, as well as the Persianovsky and Pogonovo training areas.

One of these bases, Kilmovo, is close to the Ukrainian border and less than 200 miles from Kyiv.

The map below shows the location of these bases:

Bases in Belarus are also included. They are the Brestsky, Osipovichi and Obuz-Lesnovsky training areas.

Ukrainian officials say the Russian military build-up encompasses 130,000 troops.

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