Environmental activists protested inside the lobby of BP's Houston headquarters Wednesday morning (April 15) to mark the fifth anniversary of the Deepwater Horizon rig explosion and the months-long Gulf of Mexico oil spill, FuelFix reports.

The report says more than a dozen protesters filled the atrium at BP headquarters for an hour before police attempted to remove them.

Six people were arrested, including one woman from south Louisiana, according to a statement from the Rainforest Action Network, which supported the protest.

In an emailed statement, BP spokesman Jason Ryan said activists "were politely asked to leave private property and not disrupt business."

"They refused and were escorted out by the Houston Police Department," Ryan said.

The FuelFix report says protesters were carrying signs disparaging BP for its role in the April 20, 2010, rig explosion, which killed 11 men and caused one of the worst environmental disasters in the nation's history.

More than 100 million gallons of oil spilled into the Gulf of Mexico over 87 days.