intercept
/ˌɪntəˈsept; ˌɪntɚ`sɛpt/ v[Tn]
stop or catch (sb travelling or sth in motion) before he or it can reach a destination 中途阻止或拦截（某人[某物]）
Reporters intercepted him as he tried to leave by the rear entrance. 他想从後门溜走, 记者把他截住了.
Effective defence is a matter of intercepting their missiles before they can reach us. 有效的防卫是不待对方导弹击中我们而先行将其拦截.
The police had been intercepting my mail, ie reading it before it was delivered. 警方一直截查我的邮件.