HOUSTON (AP) - A portion of the Houston Ship Channel has closed after about a dozen Greenpeace USA activists protesting the use of fossil fuels suspended themselves from a bridge ahead of a Democratic presidential debate.

The Coast Guard said Thursday that the closure came after the protesters on the Fred Hartman Bridge near Baytown were spotted. The debate is set for Thursday evening in nearby Houston.

Greenpeace activist Valentina Stackl told the Houston Chronicle , "The Democratic leadership will be here and the next president has the opportunity to lay the groundwork for a world without fossil fuels."

Harris County Sheriff Ed Gonzalez says they and other public safety partners are monitoring the situation.

The Port of Houston says the 52-mile ship channel is home to the largest petrochemical complex in the U.S.

Information from: Houston Chronicle, http://www.houstonchronicle.com

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