A group of 376 Central Americans was arrested in southwest Arizona, the vast majority of them families who used short, shallow holes dug under a barrier to cross the border, authorities said Friday. The group dug under a steel barrier in seven spots about 10 miles (16 kilometers) east of a border crossing in San Luis and made no effort to elude immigration agents. They included 176 children. The unusually large group was almost entirely from Guatemala. They were taken to Yuma after entering the country on Monday.