DENVER -- At least 900 officers are being brought into Denver to help at next month's Democratic National Convention.

Suburban Aurora will send the largest contingent, 300 police officers, or half the force.

The Wyoming National Guard will send 22 members who are trained to detect nuclear, chemical and biological weapons.

At least 582 officers have been committed from Lakewood, Littleton, Colorado Springs, Boulder, Englewood, Jefferson County, Arapahoe County and Adams County. More are expected from Douglas County, Brighton, Broomfield and Arvada.

Some will go on routine patrols with Denver police to free up the city's officers for convention work.

Denver police won't say how many officers will be working at the convention.

Thousands of protestors are expected to converge at the DNC.

On Tuesday, a federal magistrate gave Denver police and the Secret Service until Thursday to produce a map, if one exists, showing what's between the protest area in Lot A at the Pepsi Center and the entrance point for convention delegates.

By July 29, Federal District Court Judge Marcia Krieger will tour the protest areas at both Pepsi Center and Invesco Field as she rules on a lawsuit filed by the American Civil Liberties Union.

"The spots where the delegates will be has not been fully disclosed at this point, " said ACLU's legal director Mark Silverstein.