The protest took place outside Winnsboro, Texas, about 80 miles east of Dallas, said Hannah's agent, Paul Bassis.

Hannah, 51, a longtime environmental activist, was arrested last year outside the White House in another protest against the pipeline. The Keystone XL pipeline, a project of TransCanada Corp, would ship more than half a million barrels a day of oil sands-derived crude to the Texas Gulf Coast from Canada.

On Thursday, Hannah stood in front of an excavator being used to clear trees and brush in order to build the pipeline, Bassis said. Joining her was the site's property owner, Eleanor Fairchild, 78, whose land was taken by eminent domain for the project, he said.

"Ms. Hannah and Ms. Fairchild were defending Ms. Fairchild's property from eminent domain abuse by TransCanada," Bassis said.

A spokeswoman for the Wood County Sheriff's Office said no officials were available to discuss the incident.

Booking information from the Sheriff's Office said Hannah was held on charges of trespassing and resisting arrest.

A representative for TransCanada could not be reached for comment, but a company statement said the pipeline would be "safe and reliable."

The southern section of the pipeline - the project Hannah was protesting - will take oil from the glutted Cushing, Oklahoma, storage hub to refineries in Texas. President Barack Obama lent his support to the project, which is being built.

But the northern section of the $7.6 billion project, which would take crude across the Canadian border into the United States, was rejected by Obama last year on environmental and water supply grounds about its route through Nebraska.

TransCanada has reapplied to the State Department for approval of the full project. The State Department has jurisdiction because the line would cross a border.

Hannah played the mermaid in the 1984 film "Splash," and also had roles in films such as "Wall Street" and "Blade Runner."

(Editing by Alex Dobuzinskis and Peter Cooney)

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