North Korea is believed to have conducted a simulation test of what it claimed was warhead re-entry technology at a missile factory southwest of Pyongyang, a website monitoring the communist nation said Wednesday.

The North's state media released photos on March 15 of leader Kim Jong-un overseeing the simulation. Kim was also reported as saying that the country acquired the re-entry technology that is key to developing a long-range missile capable of reaching the United States.

The North did not disclose where the test took place, but the website 38 North said after comparing commercial satellite imagery and the North-released photos that it was carried out at the Chamjin Missile Factory southwest of Pyongyang.

The facility, also known as the Taesung Machine Factory, is one of the North's primary missile production facilities, 38 North said.

"By comparing the recently published photographs and commercial satellite imagery, there are several indicators that support the conclusion that this test was conducted at the Chamjin Missile Factory's vertical engine test stand," it said.

The stand, located about 500 meters southwest of the main production facility, consists of a 17-meter circular support pad connected to a 22-by-15-meter rectangular access ramp, a 25-meter-tall vertical engine test stand as well as approximately six support buildings, 38 North said.

It can hold an engine for the Scud short-range ballistic missile as well as a complete missile in the vertical position, it said. The stand can also hold a larger engine for the longer-range Rodong, although probably not a complete missile, it added. (Yonhap)