A secretary for trade minister Hiroshige Seko has been arrested for allegedly beating a taxi driver, police said Sunday.

Daisuke Kawamura, a government-paid aide to Minister of Economy, Trade and Industry Seko, is suspected of punching the driver several times in the face as he was getting out of the taxi at around 2:15 a.m. Saturday at JR Higashi-Nakano Station in Tokyo.

Kawamura, 60, who was intoxicated and had been asleep in the taxi, paid for the ride, according to the police. But the driver then restrained Kawamura when he tried to leave the car after allegedly assaulting him, and a passer-by called the police.

It is unclear why Kawamura would attack the driver, and the police did not say whether he has admitted to the allegation.

Speaking to reporters in Fukushima Prefecture, Seko offered his apologies to the driver.