The guards were ordered to shoot on sight anyone trying to escape.

卫兵接到命令，看见有谁企图逃跑就立即开枪。

《牛津词典》

Shoot on sight tactics.

积极的抢射战术。

youdao

The guard had orders to shoot on sight.

哨兵奉命见对象就开枪。

youdao

But he, along with Nicolas Anelka, who also had a shoot on sight policy, failed to trouble keeper Robert Green.

BBC: West Ham 0-1 Chelsea

Scholes and Smith were keen to shoot on sight, and Gabriel Heinze went close with a free-kick as Sir Alex Ferguson's men attempted to improve their advantage.

BBC: SPORT | Football | Premiership | Fulham 1-1 Man Utd

One of Mr Bremer's first acts was to threaten to shoot looters on sight and to ban high-ranking Baath Party members from office.

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