Real estate investment company Kennedy Wilson on Thursday said that it paid more than $143 million to acquire a large stake in a portfolio comprised of five Los Angeles-area office buildings.

The buildings are in Beverly Hills, Miracle Mile, Encino and other submarkets, according to the Beverly Hills company, which did not identify the properties to protect the seller’s identity. Kennedy Wilson’s ownership position in the properties is about 37 percent, with the remaining equity owned by Kennedy Wilson Real Estate Fund IV, Fairfax Financial and LeFrak Organization.

“These assets are premier properties in highly desirable locations,” said Mary Ricks, executive vice chairperson, in a statement. “This is the company’s first significant office acquisition in this cycle, and we were able to source this transaction off market through an existing long term relationship.”

The acquisition adds about 700,000 square feet to the company’s more than 50 million square foot portfolio, and increases total assets under management to $9.8 billion. The first of the five transactions closed on Wednesday, with the remaining transactions expected to close over the next 60 days.

Shares were up 29 cents, or 2.5 percent, to $11.87 in midday trading on the New York Stock Exchange.