DENVER -- It is once again illegal to keep a pit bull in Denver.

The animals were banned by city ordinance in 1989, but a state law passed in 2004 prohibited the singling out of certain breeds of dogs.

The city of Denver sued and In December 2004, Denver District Court Judge Martin F. Egelhoff issued a ruling that the state law violated Denver’s home rule authority under the Colorado state constitution. Egelhoff ruled that the state could not impose such limitations on Denver.

Last month, 150 Denver residents were sent letters from Denver Animal Control, warning them that the city planned to resume its ban outlawing pit bulls within city limits on Monday. More than one dozen dogs were confiscated Monday by animal control officers.

City officials estimated earlier that there were about 4,500 pit bulls kept illegally in Denver before enforcement of the ban ended last April.

Denver's pit bull law prohibits any person from owning, possessing, keeping, exercising control over, maintaining, harboring, or selling a pit bull in the City and County of Denver. A pit bull is defined in the ordinance as any dog that is an American Pit Bull Terrier, an American Staffordshire Terrier, a Straffordshire Bull Terrier, or any dog displaying the majority of physical traits of any one or more of these breeds.

Copies of the three official breed standards are available at the Denver Municipal Animal Shelter, located at 678 South Jason St. For more information, call (303) 698-0076.

Discuss: Are Pit Bulls Getting A Bad Rap?