Story highlights North Korea has fired two missiles into the sea, believed to be Scud-C

The launch comes as the United States and South Korea begin joint military drills

The annual exercises have long sparked tensions

Seoul, South Korea (CNN) North Korea has fired two short-range ballistic missiles into the Sea of Japan, a South Korean Defense Ministry official said.

The missiles were fired from North Korea's west coast into the sea, which is also known as the East Sea, around 6:30 a.m. and 6:40 a.m. Monday (4:30 p.m. and 4:40 p.m. ET Sunday), the official said.

They were fired from an area near Nampo City, located about 60 kilometers (37 miles) southwest of Pyongyang. The two projectiles were estimated to have flown about 490 kilometers (304 miles) before falling into the sea east of the peninsula, according to the South Korean official, who asked to remain anonymous citing government policy.

Considering the speed, altitude and distance the missiles traveled, they are assumed to be Scud-Cs, according to the South Korean Defense Ministry.

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