THE HAGUE, Netherlands (AP) — A Dutch court says that two directors of a poultry farm cleaning company at the center of a Europe-wide tainted food scare must remain in custody for a further 30 days while investigations into their alleged involvement in the scandal continue.

A court in the eastern city of Zwolle said Wednesday that "there are sufficient serious concerns and reasons" to extend the men's detention.

The men, whose identities have not been released, are directors of a Dutch company that allegedly illegally mixed the pesticide Fipronil into spray used to treat lice on chickens.

Millions of eggs in the Netherlands, Germany and across Europe were stripped from store shelves and destroyed after they were found to contain traces of Fipronil, which is considered a health hazard if consumed in large quantities.