Frank Manafort, of Manafort Brothers Inc., died on Sunday at the age of 78 in Florida. Manafort was born and raised in New Britain, the son of Frank and Ida Manafort. His father was one of the owners of Manafort Brothers, a well-known construction company based in Plainville. Manafort worked in the Plainville office from the mid-1950s through 2008, when he retired. During this time he was instrumental in forming the Site Work and Concrete divisions of the company, which eventually led to its role in the construction of Foxwoods and Mohegan Sun casinos. He was also responsible for aiding highway work and the construction of many of the roads and bridges in the state.