On 30 May, Bir Hakeim was quite calm; only one enemy infiltration occurred in the minefields.

Greeks bearing gifts is now a phrase recalling "enemy infiltration" and is an imputation of treachery or trickiness.

The objective was "to prevent enemy infiltration and sabotage".

Duke also assists his colleagues in defending their Yellowstone base from enemy infiltration.

He crept slowly around the perimeter of the mansion, alert to any possibility of enemy infiltration.

Support units operate in relative safety in the rear, with only the occasional enemy infiltration to worry about.

Last week, there were inspection exercises "intended to discover possible cracks in the security system" and root out "enemy infiltration," according to the Government-controlled news outlets.

Patrols are used not only on the front-lines, but in rear areas where enemy infiltration or insurgencies are possible.

Reserve assignments for infantry units involve deployment behind the front, although patrol and security operations are usually maintained in case of enemy infiltration.

The artillery of the 2d DINA could not completely check enemy infiltrations.