The United States flew a naval patrol aircraft over the Korean Peninsula, an aviation tracker said Friday, amid heightened tensions due to concerns North Korea could launch a long-range rocket.

The US Navy's P-3C maritime surveillance plane "conducted a mission over the Korean Peninsula earlier," Aircraft Spots said on its Twitter account without specifying the exact time of the operation. It also did not upload photos showing the flight route.

Recently, the US has deployed its spy planes over South Korea almost on a daily basis, sometimes several types in a day, to monitor North Korea.

On Thursday, the aviation tracker said that the US' E-8C aircraft, or JSTARS, and RC-135W Rivet Joint aircraft were spotted over South Korea. A day earlier, it uploaded three feeds regarding the detection of three aircraft -- RC-135W, Global Hawk and B-52 Bomber -- in the region.

Those flights came at a time when North Korea has threatened to take a path other than dialogue unless the US fails to come up with new proposals by the end of this year to move their stalled denuclearization talks forward.

As the latest in a series of military moves, Pyongyang conducted a rocket engine test at its Dongchang-ri satellite launching site Saturday, sparking speculation that it may be gearing up to resume testing of intercontinental ballistic missiles.

So far this year, the communist country conducted 13 rounds of major weapons tests mostly involving short-range ballistic missiles. (Yonhap)