Checking to see if one array's elements are in another array in PHP

Question

I have two arrays in PHP as follows:

People:

Array
(
    [0] => 3
    [1] => 20
)

Wanted Criminals:

Answer 1

There's little wrong with using array_intersect() and count() (instead of empty).

For example:

$bFound = (count(array_intersect($criminals, $people))) ? true : false;