crosshairs       
noun [ plural ] uk/ˈkrɒs.heəz/ us/ˈkrɑːs.herz/
 (枪支或其他仪器上帮助瞄准的)十字丝,十字瞄准线
two thin wires crossing each other in a gun or other device, which you use to help you aim at something
  A sniper had them in his crosshairs. 一个狙击手瞄准了他们。 
 The poster showed his face in the crosshairs of a rifle. 那张海报里,他的脸被放在步枪瞄准线上。 
 Idiom   
in someone's crosshairsidiom  成为……的靶子(因此会被抓住、逮捕或者阻止)
If you are in someone's crosshairs, they intend to catch, arrest, or stop you.
  He's in the law's crosshairs now. 他现在已经成为法律的靶子。