Maryland Gov. Martin O'Malley has signed a measure allowing a casino to be built in Prince George's County, just miles from the nation's capital.

The Democratic governor signed the bill Wednesday, hours after legislators passed it during a late-night special session. Voters will have the final say on the measure in November.

The law also would allow casinos to be open 24 hours and permit tables games such as poker and roulette. The bill reduces the state's high tax on slots at two casino sites to offset the financial impact of the future Prince George's County casino.