Photo/Illutration A Russian tank carrier passes through the Tsugaru Strait. (Provided by the Defense Ministry’s Joint Staff)

Russian warships carrying tanks and missile have been spotted in waters near Japan, almost certainly signaling a reinforcement of Moscow’s invasion of Ukraine, analysts said.

The uptick in Russian naval activity around Japan coincides with China’s heightened maritime presence in the region, which may reflect a degree of coordination, they added.

On March 16, Defense Ministry officials said four Russian naval transport ships were spotted in the Tsugaru Strait, which separates the main islands of Honshu and Hokkaido. The vessels were moving in a westward direction from the Pacific to the Sea of Japan.

Two Russian tank carriers were observed about 70 kilometers east-northeast of Cape Shiriya in Aomori Prefecture around 8 p.m. on March 15. Two other Russian tank carriers were spotted about 220 km east-northeast of Cape Shiriya around 7 a.m. the following day.

A Russian weapons transport ship capable of carrying missiles was spotted about 70 km east-northeast of Cape Shiriya around 9 a.m. on March 14, sources said.

The recent sightings come on the heels of a massive joint training exercise in the Sea of Okhotsk off Hokkaido that involved Russian and Chinese naval vessels.

Officials said 24 Russian vessels took part in the February exercise, a number of which were subsequently observed moving through both the Tsugaru Strait as well as the Soya Strait beyond the northern tip of Hokkaido, Japan’s northernmost main island.

Defense Ministry officials said March 14 that six Russian naval vessels, including a destroyer and three submarines, were spotted moving westward through the Soya Strait. They speculated that the ships were involved in the February training exercise.

Ten of the 24 vessels were spotted moving through the Tsugaru Strait in a westward direction on March 10 and 11.

Defense Ministry officials said it was highly unusual for such a large number of Russian naval ships to operate in waters near Japan. None of them entered Japanese territorial waters.

However, it did not go unnoticed that some of them were equipped with missiles and torpedoes.

Russia and China have engaged in joint air and sea operations in recent years.

In October 2021, defense officials noted that 10 Chinese and Russian naval vessels formed an armada to sail around the Japanese archipelago.

The fleet passed through the Tsugaru Strait to enter the Pacific before moving south and passing through the Osumi Strait south of Kagoshima Prefecture to head back to the East China Sea where the disputed Senkaku Islands are located.

Russia and China have also conducted joint surveillance flights over the Sea of Japan and East China Sea for three straight years from 2019.