1.   Also, both countries have porous borders.

2.   And with access to porous West Bank borders, Gazan immigrants will also compete for high-paying construction jobs in Israel.

3.   As many as several thousand North Koreans cross the long porous border into China each month, aid groups say.

4.   At the same time, the debate over guarding the porous borders with Canada and Mexico has never stopped.

5.   But in an age of porous borders and transcontinental flights, they move with increasing freedom.

6.   But it is in this area, along a porous border with Colombia, where Venezuelans have most to fear.

7.   But there was much speculation on whether the enemy had begun slipping across the porous border and, if so, how many.

8.   Congress tightened immigration laws, but the concern about porous borders quickly dissipated and the new rules were never put in effect.

9.   Countries with porous borders and lax passport control are often gateways for extremists who enter and then travel to neighboring capitals.

10.   Despite recent efforts to seal off the porous border, many enemy fighters are believed to have slipped across the moutain passes into Pakistan to regroup for future battles.