WASHINGTON » Chinese sculptor Lei Yixin finished removing a contentious phrase on the memorial for the Rev. Dr. Martin Luther King Jr. on Thursday in preparation for the 50th anniversary of the March on Washington at the end of the month.

The phrase came from King’s "Drum Major Instinct" speech. It read, "I was a drum major for justice, peace and righteousness."

Critics of the memorial, including the poet Maya Angelou, said the phrase did not show the true nature of the full quote. The actual quotation was: "Yes, if you want to say that I was a drum major, say that I was a drum major for justice. Say that I was a drum major for peace. I was a drum major for righteousness. And all of the other shallow things will not matter."

The quote was taken from a 1968 sermon that King delivered at Ebenezer Baptist Church in Atlanta, two months before he was assassinated.

Lei began removing the phrase Monday. Officials from the National Park Service, which maintains the memorial on the National Mall, said that Lei planned to carve grooves over the area where the phrase sat to match existing horizontal striation marks in the statute. Lei spoke at a news conference Thursday morning, using his son as his interpreter.

"He feels that it was an honor to work with the MLK foundation to make the memorial," Lei’s son, Shi Ke, said as he interpreted. "He has put a lot of effort and heart into the statute. He thinks that Americans would not regret to pick him as the sculptor."

The work is expected to be finished by Aug. 28, the 50th anniversary of the March on Washington. Park Service officials said that it could be finished before but that the date depended on the weather: The team cannot operate power tools in the rain.

Carla Johnson, a spokeswoman for the National Mall and Memorial Parks, said the Park Service was using money that had been allocated for the construction of the memorial to remove the phrase. The memorial cost $110 million to build, and the current project will run $700,000 to $900,000.

Since the memorial opened in August 2011, many critics have said the quote projected arrogance on the part of King and should also be removed because it was historically inaccurate. Lei has said he paraphrased the quote because the original was too long.

"He thought it would look better shortened," Johnson said.

She added that it was important to bring back the original team of workers because of its familiarity with the sculpture.

On Thursday, several workers stood on scaffolding erected around the memorial and used power tools on its surface. The memorial was hidden behind shrouds to prevent debris from falling on visitors.

"When people come from all over the world to visit, we know it is disappointing," Johnson said. "But a big effort here is conservation, so we have to do what we have to do."

Members of the public are allowed to visit the memorial as work continues. About 5.2 million people visited the statue last year, and park officials said people were continuing to come despite the construction.

A steady stream of tourists wandered around the memorial Thursday. They stopped to get a view of the construction and asked Park Service rangers at the statue what was going on.

"People are very moved by it, and they are still coming," Johnson said.

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