The logo of Facebook is pictured during the Viva Tech start-up and technology summit in Paris, France, May 25, 2018. REUTERS/Charles Platiau

(Reuters) - Facebook Inc opened its newest building at its Menlo Park headquarters as the world’s largest social network continues to hire aggressively to support its scorching growth.

Designed by celebrated architect Frank Gehry, the building, MPK 21, has a 3.6-acre rooftop garden featuring over 200 trees and is built with environmentally friendly materials, the company said in a blog post here on Tuesday.

The company had said in July that it was boosting its presence in London, acquiring nearly 600,000 square feet (56,000 square meters) of office space across two buildings in King’s Cross - enough for more than 6,000 workstations.

Separately, Business Insider reported that Facebook is building a physical war room to seek and destroy election meddling ahead of the U.S. midterm elections.

Last month, Facebook said it removed accounts tied to an alleged Iranian propaganda operation and took down a second campaign it said was linked to Russia.

Facebook did not immediately respond to request for comment on the Business Insider report.