my comment: There is a war raging between Syria and Iranian forces against the US forces inside Syria. Missiles and rockets are being launched and many areas destroyed. It is possible Russia is involved in defending the Syrian side.
This is a huge escalation and incursion by US forces into Syria, following several failed attempts by US forces to invade deeper inside Syria, and end up being turned away on roads inside Syria by the Russians and the local citizens.

US ground forces have the support of fighter bombers and missile defenses based in Iraq. It is anyone's guess how far Biden will take this offensive move against Syria who are still trying to defend themselves against he head choppers of ISIS.

While this is going on, US forces have a large number of navy ships in the Black sea for two weeks of military drills, including 30 NATO ships. This is after the incursion into Russia territory in Crimea, by a British ship 48 hours ago.
It appears the stage is set for a breakout of war between Russia and the US/NATO forces. Once it starts the entire eastern front will be engaged in warfare as the west tries to push against Russia. George Eaton

Article: Russia urgently withdraws all ships and submarines from the naval base in Tartus to the Mediterranean Sea

All ships and submarines of the Russian Navy, based in Tartus, were sent to intercept the NATO aircraft carrier strike group.

After Great Britain went to a very serious escalation of the situation in relations with Russia, sending its warship into the territorial waters of Russia, it became known that Russia had prepared for Great Britain much bigger problems, namely, a few hours ago from the Russian naval base in Syrian Tartus, absolutely all warships and submarines were withdrawn to the Mediterranean Sea. All of them allegedly headed to the area of ​​the carrier strike group, led by the British aircraft carrier Queen Elizabeth.

Despite the absence of official comments from the Russian Ministry of Defense, the satellite image presented shows that there is not a single warship on the territory of the Russian naval base in Syria. This fact is also due to the beginning military exercises, in which, in addition to the fleet, long-range Tu-22M3 bombers, called in the West “aircraft carrier killers” and MiG-31K fighter-interceptors, armed with “Dagger” hypersonic missiles, also capable of destroying one a direct hit to an enemy aircraft carrier.

According to experts, Russia is preparing a powerful response to the actions of Great Britain, in particular, a full-scale training of strikes against the NATO aircraft carrier strike group and the demonstrative destruction of the ship by the Dagger hypersonic missile system are not ruled out.

Source:
Подробнее на: https://avia.pro/news/rossiya-ekstrenno-vyvela-v-sredizemnoe-more-vse-korabli-i-submariny-s-bazy-vms-v-tartuse

more info on the region:
Great Britain threatens Russia with a repeat of the incident off the coast of Crimea
Подробнее на: https://avia.pro/news/velikobritaniya-ugrozhaet-rossii-povtoreniem-incidenta-u-poberezhya-kryma