An investment partnership led by Kennedy Wilson has completed acquisition of a five-building office portfolio in Los Angeles County from Jamison Services Inc. for an estimated $143 million.

The Los Angeles real estate investment and services firm said Tuesday that the partnership closed the $19 million purchase of Warner Atrium at 6400 Canoga Ave. in Woodland Hills. It’s a 126,000 square-foot complex in Warner Center.

The partnership earlier acquired 145 Fairfax Ave. in Los Angeles’ Miracle Mile, 9301 Wilshire Blvd. in Beverly Hills’ Golden Triangle; 16501 Ventura Blvd. in Encino and 9320 Telstar Ave. in El Monte.

Kennedy Wilson’s ownership position in the portfolio is approximately 37 percent, with the remaining equity owned by Kennedy Wilson Real Estate Fund IV, a separate investment fund managed by the company; Fairfax Financial Holdings Ltd., a Toronto financial services conglomerate; and LeFrak Organization, a family-run New York real estate company with limited Los Angeles holdings.

Kennedy Wilson’s press release did not disclose the seller, but company officials confirmed it was Jamison Services Inc., a large privately held commercial landlord in Los Angeles led by Korean American doctor David Lee.

Kennedy Wilson shares closed up 17 cents, or 1.6 percent, to $10.89 on the New York Stock Exchange.

Staff reporter Jacqueline Ryan contributed to this story.