PHILADELPHIA (AP) - Authorities say a teenager has died from injuries in one of a series of crashes on icy interstates in Pennsylvania that earlier claimed four lives.

State police in Pike County in northeastern Pennsylvania say a 13-year-old passenger died of injuries after he was thrown from a vehicle that overturned on Interstate 84 Sunday. The driver was also killed.

Meanwhile, Dover International Speedway officials said one of two men killed in a crash on Interstate 476 was senior director of ticket sales and operations for the track. They called 33-year-old Jason Anderson of Dover, Delaware "a dedicated husband, father, employee and friend" who "will be greatly missed." Another driver, Thomas Brennan of Lansdale, was also killed.

Another pileup involving about 60 vehicles on Interstate 76 killed 31-year-old Eric Blau of Philadelphia.