PHOENIX (AP) - An Arizona police officer and a Latino group have filed the first legal challenges of Arizona's sweeping new law on illegal immigration.

Fifteen-year Tucson police veteran Martin Escobar argues that there's no way for officers to confirm people's immigration status without impeding investigations. He filed a lawsuit Thursday in a Tucson federal court.

Separately, a Latino Clergy group filed a lawsuit in federal court in Phoenix.

The National Coalition of Latino Clergy and Christian Leaders will seek an injunction preventing authorities from enforcing the law.

The group argues federal law pre-empts state regulation of national borders, and that Arizona's law violates due process rights by letting police detain suspected illegal immigrants before they're convicted.

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