1.   Some U.S. politicians, including California Senator Dianne Feinstein, have called on Mexico to help the United States patrol the borders to prevent illegal crossings.

2.   This hut is used by a lone Russian soldier who is in charge of preventing border crossings by all unauthorized people.

3.   To prevent Chibana crossing onto his own land, the Defense Facilities Administration Agency last week surrounded the Sobe site with a fence.

4.   It mobilized its armed forces to prevent clandestine crossings, and it banned the sale of property to refugees and called on people not to rent them homes.

5.   The border post with Botswana was closed down on Tuesday preventing any crossing into Namibia.

6.   The sound of sporadic gunfire continued to ring from across the river and armed Central African Republic soldiers patrolled the river area to prevent further crossings.

7.   Burmese forces reportedly plant mines along the border to prevent illegal crossings.

8.   Officials will erect a solid-steel wall if the mesh fence fails to prevent illegal crossings, USA Today said.