Seoul (CNN)North Korea has fired a ballistic missile into the waters off the east coast of the Korean peninsula, according to officials in both South Korea and Japan.
The short range missile was fired early Sunday morning local time from the Taechon area of North Pyongan Province, according to South Korea's joint Chiefs of Staff (JCS).
It said the South Korean and US militaries are maintaining "full readiness posture" and closely cooperating following the launch.
This is the 19th missile launch this year, according to CNN's count. The last was on August 17.
Japanese Defense Minister Yasukazu Hamada said the ballistic missile may have possibly flown on an irregular trajectory.
He said the Japanese are still analyzing data on the missile but "it is estimated that it flew at a maximum altitude of about 50 kilometers (30 miles) and a distance of about 400 kilometers (250 miles) if it were a conventional ballistic missile."
"North Korea is believed to have launched at least one missile," at around 6:52am local time in Japan or 5:52pm eastern time Saturday, Hamada said.
He added it fell "near the eastern coast of North Korea", outside of Japan's Exclusive Economic Zone.
"North Korea has launched missiles 19 times this year, an unprecedentedly high frequency, including the announcement of the launch of a cruise missiles, and has also launched missiles in new responses," the Japanese defense minister said.
He added North Korea's "recent remarkable development of nuclear missile-related technologies cannot be overlooked for the security of our country and the region."
The defense minister added, "we have protested to North Korea through the embassy route in Beijing."
The US Indo-Pacific Command said there was "no immediate threat to US territory or military personnel following the launch of a short range ballistic missile in North Korea."
Japan's Coast Guard sent an alert out to vessels at 6:56 a.m. local time Sunday warning them of the missile.
"Vessels are advised to pay attention to further information and if they see any falling objects, please do not approach them and report relevant information to the Japan Coast Guard," it said.
In an update 15 minutes later it said the missile was believed to have landed in the sea.
The missile launch comes after the USS Ronald Reagan carrier strike group arrived in South Korea's southeastern port city of Busan on Friday.
The US and South Korean navy are expected to conduct combined drills this month.
The launch also comes shortly before US Vice President Kamala Harris is expected to visit Japan and South Korea.
She will stop first in Tokyo to attend a state funeral for Japan's assassinated former Prime Minister Shinzo Abe before heading to South Korea.