PARIS — Three people were released from custody Monday pending further investigation after they allegedly placed five coffins at the foot of the Eiffel Tower, a Paris landmark that will feature prominently in the upcoming Olympic Games. According to officials at the Paris prosecutor’s office, the three — citizens of Bulgaria, Germany and Ukraine — placed the coffins, covered with a French flag that included an inscription reading “French soldiers of Ukraine,” near the Eiffel Tower on Saturday. The motive for the incident was unclear. France is on its highest alert level ahead of the July 26-Aug. 11 Summer Games...