South Korea reportedly conducted the first test of a new ballistic missile with a longer range and higher payload capability last month. 

According to a government source on Thursday, the test-firing of the Hyunmoo-4 took place at the Anheung test site run by the state-run Agency for Defense Development in Taean on South Korea's west coast.

One of the two missile launches was reportedly unsuccessful.

The new missile is presumed to have a range of up to 800 kilometers and be capable of carrying a two-ton payload. 

The South Korean military began to develop the weapon in 2017 following the adoption of revised missile guidelines between South Korea and the U.S. to remove payload restrictions on South Korean ballistic missiles.