Two human arms and a human leg were found at a park on Long Island, New York, on Thursday morning, and police are investigating how they ended up there. A student was walking to school in the Long Island town of Babylon around 8:40 a.m. when she discovered a “severed left arm” at the eastern end of Southards Park Pond, which is off Siegel Boulevard, Suffolk County police said in a news release. The student then called her father, who went to the park before he called 911. A cadaver dog found a leg in a pile of leaves on the western side of the park, police said. Suffolk County police…