At 10:13 a.m Friday, a policeman began taking down the yellow crime-scene tape at the Lincoln Memorial, and a wave of visitors surged up the steps to see the damage.

The upper chamber, where the 120-ton statue of Abraham Lincoln has sat for 91 years, was still roped off. But the people could see the pale-green paint splattered on the left pant leg and the bottom of the frock coat.

A child said it looked like Play-Doh.

But the statue was solid as always. The right foot, in a square-toe boot, slightly forward. The left hand closed. The white marble face, devoid of the ravages that the Civil War etched on the human face, looked east out over the Mall.

The hallowed memorial was fully reopened at 6:30 p.m., many hours after someone splashed paint on the statue overnight and fled.

Lincoln Memorial vandalism

The National Park Service said it was the first time that the majestic memorial was vandalized since its dedication in 1922 in the presence of Lincoln’s son, Robert. It was closed briefly after the 2011 earthquake.

U.S. Park Police said they had opened an investigation but had no suspects. The police said the memorial is guarded during the overnight hours but declined to go into detail.

The Park Service said paint that had landed on the floor of the chamber had been cleaned up by mid-afternoon.

As for the statue, “there is still some residue on there,” said Carol Bradley Johnson, a spokeswoman for National Mall and Memorial Parks. “We’ll be back there Monday.”

“We’re using gentle materials to remove it,” she said. “We’re still confident that there’ll be no damage that’s permanent.”

Many visitors who gazed at the vandalism Friday seemed dumbfounded.

Young people visiting for the first time appeared especially dismayed.

“It’s disrespectful,” said Nicholas Flowers, 15, of Sunbury, Pa., as he stood at the entrance to the chamber. “That is probably one of the most rude things you can do to a great leader.”

He was in town with a school group from Pennsylvania studying leadership.

“This is probably one of the worst displays of leadership, because vandalism is just something that shouldn’t be okay,” he said.

Keashla Marengo, 23, of Bloomsburg, Pa., said: “I think it’s terrible. I don’t know why someone would do that. It is very disrespectful. And, like Nick said, it does not show leadership at all.”

Tamika Austin, 22, of Philadelphia, a senior at Bloomsburg University, said: “For my first visit, it’s kind of sad. To have to see this on my first time being here.”

Johnson called the incident “heartbreaking.”

“People come from all over the world to see [the monuments and memorials], and it’s just really disturbing that someone would do this,” she said. “The Park Service takes great pride in taking care of these national icons, and anything like this is devastating to us.”

Scattered damage has plagued Washington’s statues and monuments over the years.

The equestrian statue of Civil War Gen. George B. McClellan, at Connecticut Avenue and Columbia Road, is missing one of the original bronze shields around its base.

The original stirrups on the 1853 equestrian statue of Andrew Jackson in Lafayette Square have been missing since the 1990s.

And the D.C. War Memorial’s original metal floor medallion vanished years ago.

In 1991, protesters dumped red paint on the statue of Christopher Columbus outside Union Station and wrote “500 years of genocide.”

Seven years later, an activist carried red spray paint with her into the White House during a public tour and used it to deface a sculpture of Columbus; she was charged with felony destruction of government property.

In 2007, a type of oil was found dripped over portions of the Vietnam Veterans Memorial.

The Park Service considered the incident vandalism, but officials acknowledged that the oil might have been used by visitors in some type of ceremony. The case was never resolved.

At the Lincoln Memorial on Friday, police were reportedly reviewing surveillance footage.

[PHOTOS: View images of the paint-splattered memorial.]

Authorities believe that the memorial was defaced about 1:30 a.m. Paint was splattered on the left side and base of the 19-foot-tall statue of Lincoln, who is depicted sitting in a thronelike chair, gazing toward the Washington Monument and the distant Capitol.

Once the vandalism was discovered, Park Police closed the memorial to tourists for five hours.

[WATCH: Video of cleanup effort.]

The neoclassical memorial to the president who emancipated slaves and led the country through the Civil War was designed by Henry Bacon and modeled after an ancient Greek temple. Inscribed on the walls around the statue are Lincoln’s famous Gettysburg Address and second inaugural address.

The memorial is surrounded by 36 fluted Doric columns, representing the 36 states at the time of Lincoln’s assassination, April 14, 1865.

The memorial draws millions of visitors each year and has been the site of major moments in U.S. history.

Marian Anderson sang there on Easter in 1939 after her scheduled performance at nearby Constitution Hall was canceled because she was black.

Civil rights leader Martin Luther King Jr. delivered his “I Have A Dream” speech there on Aug. 28, 1963 — 50 years ago next month — during the famous March on Washington.

The memorial has also been the site of concerts to celebrate presidential inaugurations, including that of Barack Obama in 2009 as the nation’s 44th president and the first African American to hold the office.

David Beard contributed to this report.