Japan's financial regulator has stripped AIJ Investment Advisors of its registration as an asset manager after the company was unable to account for the bulk of $2.4 billion in pension funds, Financial Services Minister Shozaburo Jimi said.

The Financial Services Agency has also ordered Tokyo-based brokerage ITM Securities to suspend operations for six months in relation to AIJ, the minister said.

Jimi said Japan's Securities and Exchange Surveillance Commission (SESC) raided the head office of Tokyo-based AIJ and other related locations on Friday.

In one of Japan's worst financial scandals, AIJ is under investigation for falsifying performance records on roughly 200 billion yen ($2.42 billion) in pension money.

Nearly all of the money is believed to have disappeared, dealing a blow to the 84 pension co-operatives representing 880,000 employees that entrusted it with funds.

The FSA, under fire for failing to prevent the scandal, has launched an investigation into all 265 discretionary asset managers in Japan.

($1 = 82.4950 Japanese yen)

(Reporting by Emi Emoto and Chikafumi Hodo; Editing by Richard Pullin)