Hundreds of Pittsburgh-area hotel guests are back in their rooms after being evacuated because of a kitchen fire.

Officials say nobody was injured in the fire at the Holiday Inn along Route 28 in O'Hara Township, about 10 miles east of the city.

The fire was reported about 12:30 a.m. Many guests didn't respond to the initial alarm, thinking it was false. When it persisted and they filed outside, they saw smoke pouring from part of the building.

Authorities didn't immediately say how the fire started. Hotel officials say 186 rooms were full at the time and the guests have now returned.

The union local representing Pittsburgh Public Schools clerks has authorized a strike, while a union local representing custodians, truck drivers and food service workers is scheduled to take a similar vote on Saturday.The unions represent more than 500 workers combined whose last labor contracts expired in December 2006. They have worked without a contract since.Richard Caponi, an official who oversees both locals, says he's still hopeful strikes can be avoided. He says unions oppose proposed wage freezes and rules making it easier to furlough workers.A school labor official says she wasn't notified of the strike votes, may be a "ploy to disrupt" the school year.