The head of Sweden's air force is warning of Russia's "very dangerous" tactics and increased air activity in the Baltic region, Defense News reported Sunday. Amid the growing Russian presence, Sweden plans to add a number of aircraft, including its first NH90 helicopter for anti-submarine warfare.

Maj. Gen. Micael Bydén denounced tactics Russian pilots are using near Swedish airspace, reporting that Swedish air force countermeasures are up 50 percent over the last two years. "As trainee pilots we flew 10 km from borders and we expect them to do it, but after Crimea and Ukraine, the million-dollar question is 'What's next?'," Bydén said at the Paris Air Show on Sunday, according to Defense News. "I grew up with it, but this is unpredictable and I don't like the development."

Bydén pointed out two close calls involving civilian planes leaving from Copenhagen airport in Denmark and Russian aircraft called IL-20s. "In March 2014 an IL-20 came within 300 feet of a Scandinavian Airlines aircraft, and there was a similar incident in December," he said, according to Defense News. The December incident reportedly required intervention from military air-traffic controllers, who warned the civilian aircraft to change its course. The IL-20 incidents followed a March 2013 situation in which six Russian aircraft ran a mock bombing run near Swedish airspace.

Sweden has also made plans to acquire new aircraft. The Swedish military will add its first NH90 helicopter for anti-submarine warfare in the fall, reported Defense News. The acquisition comes after a long delay. "We have not been pleased with this program, it is very late," said Swedish procurement chief Lena Erixon, according to Defense News. "With what is happening in the Baltic, it is very important."

An unidentified submarine, possibly Russian, was spotted in waters around Stockholm last October, reported Defense News. The submarine's entry into the capital city's archipelago was a violation of their territory, the Swedes said. The new NH90 is part of a larger order of 18, and Sweden aims to have "final operating capability" for the NH90 -- complete with five new aircraft -- in three to five years, according to Defense News.

Along with the helicopter purchases, Sweden plans to add 60 Gripen E jets by 2022, according to Defense News. The upgraded aircraft will reportedly reach full operational capacity by 2026. An original plan to upgrade existing Gripen jets is now being reconsidered, and the aircraft might be built from scratch.

Russian aircraft recently made news for coming within 10 feet of a U.S. spy plane last month. The European Leadership Network released a report saying Russian aircraft have increasingly harassed U.S. and NATO reconnaissance aircraft.