The prosecution is set to question Hyosung Group chairman Cho Suck-rai on Tuesday as part of an investigation into the company’s alleged tax evasion, slush funds and accounting fraud, officials said Monday.

The Seoul Central District Prosecutors’ Office has summoned Cho to appear at 10 a.m. Tuesday. He will be the third person from the family to be questioned.

Hyosung is Korea’s 26th largest business group, with assets of more than 11 trillion won ($10.4 billion).

Prosecutors are expected to grill Cho about whether he was directly involved in the accounting fraud and tax evasion, which together involved about 100 billion won.

The prosecution has sped up the probe since October over the conglomerate’s tax evasion and embezzlement schemes, which allegedly involved accounting fraud and amassing slush funds overseas.

It questioned the chairman’s eldest son, Cho Hyun-joon; the second son, Cho Hyun-moon; and the group’s vice chairman Lee Sang-woon toward the end of last month.

The National Tax Service launched a special tax audit in May in which it uncovered the alleged tax evasion. It banned Cho and other executives from leaving the country and reported the allegations to the prosecution in September.

By Lee Hyun-jeong (rene@heraldcorp.com)