Several blocks away, they saw a suspect, who fled at their approach.

We will be searching for any small boats which look suspicious or attempt to flee at our approach.

A cat jumped off a stone wall and fled at his approach.

Dark things fled into a woods at the bird's approach.

The two younger children were terrified of him and fled at his approach.

A youth on a bicycle fled at their approach.

People in the street fled at their approach.

My father met the poor creature, who fled at his approach.

Here was something which fled aside at his approach.

If anyone had been there, they had fled at his approach.