Union workers, supporters march through San Francisco over contract negotiations

SAN FRANCISCO (KGO) -- Hundreds of janitors with Service Employees International Union Local 87 whose contract expired over the weekend are holding a rally today in San Francisco in support of better wages and benefits.

Janitors rallying to push for a new contract blocked traffic at Market and Kearny streets.

Union members voted last week to authorize a strike if negotiations stalled.

Their contract expired at midnight, but the two sides are continuing to try to work out a deal.

The janitors work in various office buildings throughout the city.

Bay City News contributed to this story.