Mexican soldiers and civilian smugglers had an armed standoff with nearly 30 U.S. law enforcement officials on the Rio Grande in Texas on Monday afternoon, according to Texas police and the FBI.

Mexican military Humvees were towing what appeared to be thousands of pounds of marijuana across the border into the United States, said Chief Deputy Mike Doyal, of the Hudspeth County Sheriff's Department.

Mexican Army troops had several mounted machine guns on the ground more than 200 yards inside the U.S. border -- near Neely's Crossing, about 50 miles east of El Paso -- when Border Patrol agents called for backup. Hudspeth County deputies and Texas Highway patrol officers arrived shortly afterward, Doyal said.

...An FBI spokeswoman confirmed the incident happened at 2:15 p.m. Pacific Time...