Prosecutors said Thursday they have decided not to indict former Prime Minister Shinzo Abe over allegations his camp illegally paid millions of yen for dinner receptions held for supporters, ending their investigation into a scandal that came to light last year.

They instead issued a summary indictment to one of Abe's state-paid secretaries, Hiroyuki Haikawa, 61, seeking a fine for his alleged failure to keep some financial records related to the dinner functions as required by law.

"Although those expense accounts were handled without my knowledge, I'm painfully aware of collective responsibility," Abe told a news conference Thursday evening. "I'm going to profoundly reflect on it and I apologize to the public from the bottom of my heart."