A piece of the crashed Malaysia Airlines Flight 17 lies in the grass near the village of Hrabove, eastern Ukraine, Saturday, July 19, 2014. World leaders demanded Friday that pro-Russia rebels who control the eastern Ukraine crash site of Malaysia Airlines Flight 17 give immediate, unfettered access to independent investigators to determine who shot down the plane. (AP Photo/Evgeniy Maloletka)

Rebels hamper access to plane crash site

Armed separatists hampered access to the Malaysia Airlines crash site Saturday, limiting the movements of international monitors and raising…