Banner reading 'Refugees welcome' appears at base of Statue of Liberty Affixing a banner to the monument is illegal.

 -- A banner reading "Refugees welcome" was put up illegally on the base of the Statue of Liberty Tuesday afternoon, authorities said.

The banner, 3 feet by 20 feet, was unfurled atop the pedestal around 12:50 p.m., according to National Park Service police. It was affixed to the outside of the public observation deck at the base of the statue by nylon rope.

When alerted to the presence of the banner, park rangers immediately made their way to the location to assess how to get it down. They were able to remove it without damaging the monument.

Visitors began posting photos to social media soon after the banner appeared.

The National Park Service said affixing signs to the Statue of Liberty or its pedestal is "strictly prohibited" and that an investigation is underway to identify the people who placed the banner there.