The following is a chronology of major events leading to North Korea's first attempt to put into orbit what it called its first military spy satellite.

The North launched what it claims to be a "space launch vehicle" southward Wednesday, but it fell into the Yellow Sea after an "abnormal" flight, the South Korean military said.

The North confirmed the failure but said it plans to conduct a second launch as soon as possible.

January 2021 ― North Korea lays out plans to develop a military spy satellite as one of its key defense projects during the eighth congress of the ruling Worker's Party of Korea (WPK).

Feb. 27, 2022 ― North Korea launches a ballistic missile and announces the next day that it has carried out an "important test" to develop a reconnaissance satellite.

March 5, 2022 ― North Korea says it has conducted another "important test" for developing a "reconnaissance satellite."

March 10, 2022 ― North Korean leader Kim Jong-un visited the country's space development agency and vowed to put "a lot of" military satellites into orbit in the next five years, according to the Korean Central News Agency (KCNA).

North Korea's spy satellite launch fails as rocket falls into sea 2023-05-31 15:59  |  North Korea NK's attempt to launch 1st spy satellite fails after 'abnormal' flight: S. Korean military 2023-05-31 07:07  |  North Korea

An undated photo, released on March 11, 2022 by the official North Korean Central News Agency (KCNA), shows Kim Jong-un, center, general secretary of the Workers' Party of Korea (WPK) and president of the State Affairs of the Democratic People's Republic's Republic of Korea inspecting the Sohae Satellite Launching Ground in Tongchang-ri, North Pyongan Province, North Korea. EPA-Yonhap

March 11, 2022 ― The KCNA reports the North's leader inspected the Sohae Satellite Launching Ground and set forth the task to modernize the launching ground so that "various rockets could be launched to carry multi-purpose satellites."

Dec. 18, 2022 ― North Korea conducts an "important final-stage" test at its rocket launching facility on putting a military reconnaissance satellite into orbit, with a plan to complete preparations for the project by April 2023.

April 18, 2023 ― Kim Jong-un visits the North's space development agency, where he declares that Pyongyang has completed building its first military spy satellite and orders officials to prepare for the satellite launch as planned.

May 16, 2023 ― Kim Jong-un visits the Non-permanent Satellite Launch Preparatory Committee and approves of its "future action plan."

May 29, 2023 ― North Korea notifies Japan of its plan to launch a satellite between May 31-June 11.

May 30, 2023 ― Ri Pyong-chol, vice chairman of the Central Military Commission of the ruling WPK, says North Korea will launch its military spy satellite in June.

May 31, 2023 ― North Korea launches its military reconnaissance satellite "Malligyong-1," mounted on a new-type rocket named "Chollima-1," at its rocket launching station on the west coast, but the launch ends in failure.