SEOUL - South Korean prosecutors indicted former president Moon Jae-in for alleged bribery on Thursday, making him the latest former leader of the country to face legal troubles in a case linked to the appointment of his then son-in-law at a Thai airline.

Moon, 72, was indicted for bribery, while in the same case former lawmaker Lee Sang-jik was indicted for bribery and breach of trust, Jeonju District Prosecutors' Office said in a statement.

Prosecutors had been investigating whether Lee's appointment as the head of the SMEs and Startups Agency was in exchange for Moon's former son-in-law getting a job and receiving a salary plus living expenses at the Thai-based corporation that Lee controlled in 2018-2020, the statement said.

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The prosecution alleges that the money Moon's son-in-law received as an executive director, totalling 5.95 million baht ($177,506), was irregular and constituted a bribe to the then-president.

Prosecutors referenced previous bribery cases involving former presidents Park Geun-hye and Lee Myung-bak, both of whom were convicted and jailed, as precedents for Moon's indictment.

Moon, Lee and their legal representatives could not immediately be reached for comment.

Youn Kun-young, a lawmaker and a close aide to Moon, accused the prosecution in a Facebook post of setting Moon up through "ridiculous and groundless charges" without properly investigating him.

The liberal-leaning Moon, a lawyer and a civil rights activist, was president between 2017 and 2022.

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Over the last two decades, a string of South Korean leaders have faced trials or scandals for the most part toward the end of their terms or after leaving office.

Moon's successor, Yoon Suk-yeol, was removed from office this month after being impeached over his short-lived imposition of martial law. The conservative former leader, who had denied wrongdoing, is now on trial on criminal charges of insurrection.

South Korea is holding a snap election to pick a new leader on June 3, with the liberal-leaning Lee Jae-myung from the same Democratic Party as Moon the frontrunner in opinion polls to win the race.

Lee's campaign called Moon's indictment political retribution by the prosecution and a crackdown on the previous administration.