TORONTO -- Onex Corp. (TSX:OCX) says it has agreed to acquire risk management firm York Risk Services Group Inc. for US$1.33 billion.

The Toronto-based private equity firm says the transaction is expected to close in the third quarter.

York Risk Services provides property, casualty, and workers' compensation insurance to more than 6,300 clients in the United States.

The firm is based in Parsippany, N.J., and says it has handled claims for all of the major hurricanes over the past 40 years, as well as claims from the World Trade Center attacks on Sept. 11.

York Risk Services has 3,800 employees based in 75 offices.

Onex will make an equity investment of about $560 million through its Onex Partners III investment fund, with other partners as co-investors, including management from both companies.

Onex manages approximately US$19 billion in private equity assets, credit securities and real estate.