DETROIT (AP) -- Thousands of union supporters have marched through downtown Detroit as part of a Labor Day celebration that includes an address by Vice President Joe Biden.

The annual Metro Detroit AFL-CIO Labor Day parade started under sunny skies Monday morning, followed by a rally featuring Biden. His speech will be only the latest of several he's given in Michigan this summer.

Biden addressed the American Federation of Teachers' national convention in Detroit on July 29 and spoke at a rally at Detroit Renaissance High School on Aug. 22 during a Michigan stop that also included fundraising events.

The Labor Day appearance comes ahead of the Democratic National Convention in Charlotte, N.C.

President Barack Obama appeared at Detroit's Labor Day parade in 2011.

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