A Russian fighter jet on Monday reportedly intercepted and escorted U.S. and Norwegian patrol aircraft over the Barents Sea.

The Russian Defense Ministry said the incident over the body of water near Sweden, Norway, Finland and Russia involved a MiG-31 fighter jet, Reuters reported, citing Russias state-run RIA news agency.

The Hill has reached out to the Pentagon for comment.

The move comes after a Russian MiG-31 last week escorted a U.S. reconnaissance aircraft along the countrys far northeast Kamchatka Peninsula over the Pacific Ocean, according to Russian news agency Tass.

Moscow in the past month has heightened its military presence in the region, particularly at its border with Ukraine and in the Black Sea, with Russian jets and bombers frequently flying near allied airspace.

Fighting has increased in eastern Ukraine with pro-Russian separatists. Biden administration officials have confirmed that Russia now has more troops on the border with Ukraine than at any time since 2014 when it annexed Crimea.

President BidenJoe BidenGraham: ‘I could not disagree more’ with Trump support of Afghanistan troop withdrawalObama, Shaquille O’Neal, Charles Barkley team up to urge communities of color to get coronavirus vaccineBiden to hold second meeting with bipartisan lawmakers on infrastructure MORE last week raised concerns with Russian President Vladimir PutinVladimir Vladimirovich PutinSullivan: ‘There will be consequences’ if Navalny diesMacron: Russian presence at Ukraine border is ‘absolutely counterproductive and unacceptable’Doctor says Navalny could die ‘at any moment’MORE about escalating tensions in Ukraine in a phone call where he emphasized the United States unwavering commitment to Kyiv.

The recent aircraft incidents come less than a week after the Biden administration announced sanctions targeting several Russian officials and companies, and the expulsion of 10 Russian diplomats, as punishment for election meddling and the countrys involvement in the SolarWinds hack, which Russia has denied.

In response, Moscow expelled 10 Americans from Russia.