An artificial intelligence expert lost the chance to be South Korea’s first citizen in space after reading and removing manuals from Russia’s cosmonaut training center without authorization, the government said Monday. Instead, a female bioengineer will conduct scientific experiments on a Russian voyage to the International Space Station next month, the South Korean Ministry of Education, Science and Technology said.

Ko San — the original choice — repeatedly violated regulations at the training center was replaced by Yi So-yeon, a 29-year-old woman with a doctorate in bioengineering who had been South Korea’s second choice for the mission.

Russian authorities said Ko took his training manual out of the center without permission and sent it to his home in South Korea in September, Lee said. Ko later returned the manual, explaining he accidentally sent it home together with other personal belongings, Lee added.

In February, Ko again broke the rules by getting what was believed to be a manual used by space pilots from the center through a Russian colleague — material he was not supposed to read, Lee said. Ko had signed the center’s instructions on the rules.

Anatoly Perminov, chief of the space agency, said in a statement on its Website Monday that the change was because Ko “violated the code of conduct for cosmonauts,” adding that the substitution would cause no complications for the mission.

Yi is scheduled to work aboard the space station for about 10 days with five other cosmonauts, including an American woman, according to Lee’s ministry.

The Soyuz spacecraft is scheduled to lift off from a space center in Baikonur, Kazakhstan, on April 8, the statement said. The mission will make South Korea the world’s 36th country to send an astronaut into space, said ministry official Kim Ki-seok.