In this Feb 16, 2017 file photo, Samsung Electronics Vice Chairman Jay Y. Lee (front) enters a Seoul court for hearings in Seoul, South Korea. (LEE SANG-HO / XINHUA)

SEOUL - South Korean prosecutors have requested an arrest warrant against Samsung Group heir Jay Y. Lee and two former company executives, they said on Thursday, in an investigation of a controversial 2015 merger and alleged accounting fraud.

The move spells fresh legal trouble for Lee, who already faces trial on a charge of bribery aimed at winning support to succeed ailing group patriarch Lee Kun-hee

The move spells fresh legal trouble for Lee, who already faces trial on a charge of bribery aimed at winning support to succeed ailing group patriarch Lee Kun-hee, and which involved former President Park Geun-hye.

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Prosecutors said the warrant against Lee was sought on suspicions of stock price manipulation, among other offences.

Samsung declined to comment.

Lee, 51, spent a year in detention until the bribery case was suspended in 2018, but the possibility of a tougher sentence has emerged after the Supreme Court overturned a lower court ruling on the case last year.

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Prosecutors have been investigating suspected accounting fraud at drug company Samsung Biologics after the Korean financial watchdog complained the firm’s value had been inflated by 4.5 trillion won (US$3.7 billion) in 2015.

Last month, Lee was questioned by prosecutors investigating the accounting fraud accusation and a controversial 2015 merger they said may have helped him advance his succession-planning agenda at South Korea’s top conglomerate.