NEW YORK (CBSNewYork) — Former New York City Mayor Ed Koch continues to undergo tests after being admitted into the hospital for anemia.

Koch is said to be doing well and in excellent spirits but was not released from the hospital Wednesday as he had originally hoped,

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The 87-year-old was admitted to New York Presbyterian Hospital and underwent a blood transfusion Tuesday morning after he began feeling weak over the weekend while staying with friends in North Carolina, a spokesperson said.

WCBS 880’s Paul Murnane reports

The three-term mayor has had previous health issues, including a stroke, a heart attack and quadruple bypass surgery.

He is a fixture in New York City who is best known for saving it from the brink of bankruptcy in the early 1980s. Since leaving office in 1989, he’s stayed on the front lines of politics — launching a campaign against corruption in Albany two years ago.

Koch continues to practice law. He also hosts a radio show, writes a newspaper column and served as a judge on “The People’s Court” for two years.

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Last year, the Queensboro Bridge was named after him.

Many New Yorkers are now wishing their beloved former mayor a speedy recovery.

“I wish him all the best. I was just sitting in the cafe the other day and I saw him eating, drinking a chocolate shake, people taking photos with him. Really pleased to see him and I was thinking, he really is a New York monument,” said Upper West Side resident Bob Sarlin.

“I wish him well and trust that he comes back,” said Upper West Side resident Richard Sheely. “He’s a strong old devil and if anyone can come back, he will.”

Anemia is a condition in which the body does not have enough healthy red blood cells. Some symptoms include headaches, weakness and dizziness.

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