ORLANDO, Fla. (AP) - Two members of Congress are challenging a new amendment that sets rules for drawing congressional districts in Florida, less than 24 hours after it was approved by voters.

U.S. Reps. Corrine Brown and Mario Diaz-Balart filed a lawsuit challenging Amendment 6 Wednesday in federal court in Miami. The lawsuit asks that the amendment be declared invalid and stopped from being enforced.

They claim the new standards could threaten Florida's six congressional districts where blacks and Hispanics are either the majority or close to being in the majority, a contention strongly disputed by the amendment's supporters.

The amendment requires districts be compact, equal in population and make use of existing city, county and geographical boundaries.