Federal agents swept through a chicken processing plant Tuesday, detaining more than 300 suspected illegal immigrants, sending panicked workers running and screaming through the hallways. Worried relatives collected outside, fearful their loved ones would be deported.

Police and agents during a shift change ordered all workers at the House of Raeford's Columbia Farms to show identification, according to officials and witnesses. The business had been under scrutiny for months and the raid comes on the heels of even larger roundups at plants across the country...