Roadrunner Transportation Systems Inc. (NYSE: RRTS) is buying Unitrans International Logistics for an undisclosed amount.

Unitrans, headquartered in Inglewood, Calif., provides international shipping and logistics services, including ocean and air transportation management, customs house brokerage and domestic logistics services.

Private equity firm Palm Beach Capital and fundless sponsor Logisticap Partners sold Unitrans.

Roadrunner provides transportation and logistics services, including less-than truckload, truckload, transportation management, freight consolidation, inventory management and other services. In August, the company bought assets from Transport Corporation of America Inc., and in July, bought Marisol International LLC

Roadrunner is one of several logistic companies that have been consolidating the industry. For more, see "7 Savvy Strategic Buyers."