Updated

South Korea said Monday a female engineer would become the country's first person in space by going aboard a Russian spacecraft, after Moscow rejected Seoul's first choice because he violated reading rules during training.

The Ministry of Education, Science and Technology said at a news conference that Yi So-yeon will replace Ko San as the country's choice to fly on a Russian Soyuz capsule to the International Space Station in early April.

South Korea originally named Ko as its candidate in September, but Russia's Federal Space Agency asked for a replacement last month because he violated regulations at a Russian space training center where the two South Koreans have been training, said Lee Sang-mok, a senior ministry official.

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The Russian authorities said Ko took a book out of the center without permission and sent it to his home in South Korea in September, Lee said.

Ko later returned the book, explaining he accidently sent it home together with other personal belongings, Lee added.

In February, Ko again violated a regulation by getting a book from the center through a Russian colleague — material he was not supposed to read, Lee said.

Officials did not give details about the book's contents, but South Korean officials portrayed both of his infractions as minor.

"The Russian space agency has stressed that a minor mistake and disobedience can cause serious consequences," Lee told reporters.

Ko will remain at the Russian space center and train with Lee, the ministry official said.

Yi, 29, will work aboard the International Space Station for about 10 days with five other cosmonauts including one female American astronaut, conducting scientific experiments, according to a ministry statement.

The mission will make South Korea the world's 35th country and Asia's sixth to send an astronaut into space.

Yi, currently employed by the Korea Aerospace Research Institute, earned both bachelor's and master's degrees in mechanical engineering at the state-run Korea Advanced Institute of Science and Technology, according to the ministry statement.

In February, she received her Ph.D. in a bioengineering from the same school.

"The honor to become South Korea's first astronaut will belong to a woman, when and if Yi eventually goes aboard the Soyuz capsule," Lee said.

A total of 48 women from the United States, Russia and four other countries have so far gone into space, the ministry statement said.

South Korea plans to complete its first space center by the end of next year as part of a program to lay the technological and scientific groundwork for space exploration in coming decades.

Since 1992 South Korea has had 11 satellites launched, mostly for space and ocean observation and communications.