Infiltrate

прони́кнуть

proníknutʹ

(to surreptitiously penetrate, enter or gain access)

проника́ть

pronikátʹ

(to surreptitiously penetrate, enter or gain access)

проникать в тыл противника

pronikatʹ v tyl protivnika

(to send soldiers through gaps in the enemy line)

проникнуть в тыл противника

proniknutʹ v tyl protivnika

(to send soldiers through gaps in the enemy line)

проса́чиваться

prosáčivatʹsja

(to surreptitiously penetrate, enter or gain access)

просочи́ться

prosočítʹsja

(to surreptitiously penetrate, enter or gain access)