NEWPORT BEACH (CBS) — Funeral plans were pending Sunday for Donald Koll, the developer behind many of Orange County’s office complexes and who built the equivalent of 30 Empire State Buildings.

Koll, 78, died of a heart attack Tuesday.

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Koll Co. and its affiliated firms built more than 90 million square feet of commercial space, according to a company spokesman.

Koll founded the company in 1962 and specialized in building custom homes. His firm also built a replica of Independence Hall at Knott’s Berry Farm.

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Building warehouses and office buildings near the then-small Orange County Airport led Koll to start building massive office centers, such as the Koll Center Newport.

The firm also built the Hughes Aircraft Corporate Headquarters perched over Ballona Creek in Westchester, now the headquarters of Loyola Marymount University, and the Carlsbad Research Center, the largest research and development center of its kind in San Diego County.

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