Highway employees working around a bridge in Belén uncovered a stash of three rifles Monday. They were hidden under a bridge and protected by a plastic bag.
The weapons included an M-14, and AK-47 and a Galil, an Israeli-manufactured rifle. Also discovered was ammunition.
The Fuerza Pública said that the weapons were capable of automatic firing. Such weapons are illegal in Costa Rica., although they are traditional weaponry of drug gangs.