Constructora Nacional de Carros de Ferrocarril SA, known as Concarril, or less commonly as CNCF, was a government-owned major rail vehicle manufacturer located in Ciudad Sahagún, Mexico, from the 1950s through 1991. It manufactured a wide variety of passenger and freight cars, as well as locomotives. Formed in 1952 (some sources say 1954), it was owned by the Mexican government. After accumulating too much debt, it ceased operating in December 1991 and was sold to Bombardier, Inc. in April 1992 for around U.S.$68 million. At that time, it was the largest manufacturer of railway rolling stock in Mexico. Production resumed at the Ciudad Sahagún facilities after Bombardier took over.