BALTIMORE — FRP Development Corp., a Baltimore-based development and investment company, has sold 40 industrial warehouse properties and three adjacent land parcels in the Baltimore-Washington corridor for $347.2 million. Blackstone Real Estate Partners acquired the assets. Another warehouse property in the portfolio was sold to its current tenants for $11.7 million. The sale of the portfolio will allow FRP to focus on its development pipeline in the metropolitan region, according to David deVilliers Jr., the company’s president and COO. The developer is currently underway on RiverFront on the Anacostia, a four-phase, 1.1 million-square-foot mixed-use development located adjacent to Nationals Park in Washington, D.C. In partnership with St. John Properties, FRP is also developing a 330,000-square-foot office and retail project in Baltimore County. FRP is a wholly owned subsidiary of FRP Holdings Inc., a Florida-based company that also comprises Florida Rock Properties Inc.