The federal WARN Act (Worker Adjustment and Retraining Notification Act) almost certainly applies here. It requires employers with 100+ employees to provide 60 days written notice before a plant closing or mass layoff affecting 50+ employees at a single site.
Penalties for violation: Back pay and benefits for up to 60 days (the notice period they should have given). For 200 employees, this adds up fast — potentially millions in aggregate.
Exceptions are narrow: (1) "Faltering company" — seeking capital that would have been jeopardized by notice (rarely successful defense), (2) Unforeseeable business circumstances, (3) Natural disaster. The employer bears the burden of proving an exception applies.
Reversed direct deposits: This is a separate issue — clawing back wages already paid may violate state wage payment laws independently of WARN.
WARN Act claims are commonly brought as class actions. Contact an employment attorney — these cases typically proceed on contingency because the damages are calculable and liability is often clear.