MPG Office Trust Inc. on Monday said that it has disposed of City Tower in the city of Orange, in cooperation with the special servicer on the mortgage loan.

The Southern California real estate investment trust, which has been unloading non-core properties to reduce debt, said it is relieved of the obligation to repay $140 million mortgage loan secured by the property, as well as contractual and default interest. MPC did not identify the new owner of the property, which is a 21-story, 410,000 square-foot office tower built in 1988.

In a separate announcement, MPG said it signed an agreement to exchange 218,635 shares of its 7.625-percent Series A cumulative redeemable preferred stock for nearly 1.13 million shares of its common stock. The company did not identify the shareholder or shareholders involved in the deal.

Shares were down 14 cents, or 3.8 percent, to $3.56 in midday trading on the New York Stock Exchange.