NOGALES, Ariz. (AP) — A new type of border fence is apparently forcing drug smugglers to change the way they move their cargo from Mexico to the U.S.

The Nogales International reports that law enforcement officers in Arizona recently noticed that some bundles of marijuana they seized were oddly shaped.

Lt. Gerry Castillo of the Santa Cruz County Metro Task Force says investigators first thought the 48 pounds of marijuana wrapped in thin tubular packages had been prepared for easy transport through a tunnel. But the bundles
weren’t dirty.

That’s when investigators realized the packages had likely been passed between the bars of the new border fence. It features concrete-filled steel tubes with an approximately 4-inch space between them.

The new $11.6 million, 2.8-mile fence near Nogales was completed this summer.