Story highlights Dutch spokesman: 2 Russian bombers enter Dutch airspace by a half mile

2 F-16 Dutch fighter jets intercept the Russian planes, escort them away

British military jets later become involved; action is called "not unusual"

But it comes amid heightened tensions between Russia and NATO

Dutch fighter jets scrambled Wednesday to intercept a pair of Russian military aircraft that entered their airspace, a fairly routine action that comes amid heightened tensions between Russia and NATO, a Dutch official said.

Maj. Wilko Ter Horst said that the military learned around 3:50 p.m. (9:50 a.m. ET) that two Russian TU-95 bombers, known as Bears, had come a half-mile inside its airspace.

A pair of Dutch F-16 military jets were then dispatched to escort the Russian planes and "ensure they (flew) out of our airspace," said Ter Horst, a Dutch military spokesman.

Such a sequence of events isn't uncommon, with the Netherlands military spokesman explaining "this is a national procedure when aircraft infringe (on) national Dutch airspace." He estimated Dutch fighter jets scramble to check out unknown aircraft -- be they from Russia or another country -- about four or five times a year.

"It is not unusual," Ter Horst added. "Sometimes they cross Dutch airspace and sometimes they stay north of Dutch airspace (in the country's so-called area of responsibility)."

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In this case, British military aircraft took over from the Dutch in escorting the Russian planes.

A British Defense Ministry spokesman said that planes from his military left from Royal Air Force station Leuchars "to determine the identity of unknown aircraft that approached the NATO Air Policing Area north of Scotland and could not be identified by other means."

These planes were later identified as the Russian military planes. The spokesman stressed that they didn't enter British airspace, nor has any Russian military plane ever done so.

"The Russian military aircraft remained in international airspace at all times, as they are perfectly entitled to do," the spokesman said.

In a separate and "standard" event, Britain's HMS Dragon met up with the Russian ship Vice Admiral Kulakov as it was "transiting past the UK," according to the military spokesman. The British naval destroyer is now "keeping an eye on its transit south," he added.

There was no immediate mention of this story on the English-language versions of at least two Russian state-run media outlets, RT and RIA Novosti.

While British Defense Secretary Philip Hammond said his military is always on alert "to intercept any non-NATO forces," he did not portray these specific incidents as alarming.

"Recent events have increased awareness of Russian military activity," Hammond said. "But we have always routinely intercepted, identified and escorted Russian air and naval assets that transit international airspace and waters within the UK's 'area of interest.'"

Both the Netherlands and the United Kingdom are part of NATO, which has been increasingly at odds with Russia over its activity in and around Ukraine

The tensions ratcheted up late last year, when demonstrators pushed out Ukraine's president in part due to their anger about his moving away from an alliance with Europe and moving closer to Russia.

A pro-Western government took over in Kiev. Soon after, the Crimean peninsula seceded from Ukraine and became part of Russia.

Since then, Russia has deployed what NATO estimates to be 40,000 troops near its border with Ukraine, which has made other countries in the area nervous.

In an interview Wednesday with RT, Russian Foreign Minister Sergey Lavrov said that Russia would "certainly respond" if its interests were attacked in Ukraine.

"Russian citizens being attacked is an attack against the Russian Federation," Lavrov said.