__________________________I'm Frances Alonzo reporting from Washington. US federal investigators have searched an apartment in the Suburban Boston town of Revere as part of the effort to find who was behind the bombing Monday at the Boston marathon. Three people were killed in the incident and more than 140 people are wounded. Investigators were seen removing items from the apartment, no arrest have been made. Meanwhile, no group or person has claimed responsibility. ___________________我是Frances Alonzo,华盛顿报告. 美国联邦探员搜查了波士顿郊区里维尔小镇的一所公寓,这是调查波士顿马拉松爆炸案幕后黑手的一部分.该爆炸造成三人死亡,另有超过一百四十人受伤.有人看到调查人员移除了公寓内的物品,但还没有人被捕.同时,尚无组织或个人宣称对此事负责.