House Speaker Nancy Pelosi rushed to the defense of Rep. Elijah Cummings after President Trump criticized the black lawmaker and called his Baltimore-based district a "disgusting, rat and rodent infested mess."

"[Cummings] is a champion in the Congress and the country for civil rights and economic justice, a beloved leader in Baltimore, and deeply valued colleague. We all reject racist attacks against him and support his steadfast leadership," the California Democrat tweeted along with the hashtag #ElijahCummingsIsAPatriot.

.@RepCummings is a champion in the Congress and the country for civil rights and economic justice, a beloved leader in Baltimore, and deeply valued colleague. We all reject racist attacks against him and support his steadfast leadership. #ElijahCummingsIsAPatriot https://t.co/2LG8AuQrHh — Nancy Pelosi (@SpeakerPelosi) July 27, 2019

After Trump claimed Cummings' district in Maryland was "more dangerous" than the U.S.-Mexico border, the Democratic leader defended his record of working for his constituents.

"Mr. President, I go home to my district daily. Each morning, I wake up, and I go and fight for my neighbors. It is my constitutional duty to conduct oversight of the Executive Branch. But, it is my moral duty to fight for my constituents," Cummings said.

Just yesterday, I held a hearing on the skyrocketing prices of prescription drugs and the financial hardships that families across the nation, and in Baltimore, are facing. — Elijah E. Cummings (@RepCummings) July 27, 2019

"Just yesterday, I held a hearing on the skyrocketing prices of prescription drugs and the financial hardships that families across the nation, and in Baltimore, are facing," he added. "Mr. President, we can address this together. Two years ago, I went to the White House to ask you to endorse my bill to let the government negotiate directly for lower drug prices. You told me then that you supported the legislation and that you would work with me to make it happen. I took you at your word."

You told me then that you supported the legislation and that you would work with me to make it happen. I took you at your word.https://t.co/bcfyQgXwm4 — Elijah E. Cummings (@RepCummings) July 27, 2019

Cummings has represented the 7th Congressional District since 1996.

In a trio of tweets Saturday morning, Trump called Cummings a "brutal bully" and described his district as a "disgusting, rat and rodent infested mess."

"Rep, Elijah Cummings has been a brutal bully, shouting and screaming at the great men & women of Border Patrol about conditions at the Southern Border, when actually his Baltimore district is FAR WORSE and more dangerous. His district is considered the Worst in the USA," Trump said. "As proven last week during a Congressional tour, the Border is clean, efficient & well run, just very crowded. Cumming District is a disgusting, rat and rodent infested mess. If he spent more time in Baltimore, maybe he could help clean up this very dangerous & filthy place."

....As proven last week during a Congressional tour, the Border is clean, efficient & well run, just very crowded. Cumming District is a disgusting, rat and rodent infested mess. If he spent more time in Baltimore, maybe he could help clean up this very dangerous & filthy place — Donald J. Trump (@realDonaldTrump) July 27, 2019

"Why is so much money sent to the Elijah Cummings district when it is considered the worst run and most dangerous anywhere in the United States. No human being would want to live there. Where is all this money going? How much is stolen? Investigate this corrupt mess immediately!" he said.

Why is so much money sent to the Elijah Cummings district when it is considered the worst run and most dangerous anywhere in the United States. No human being would want to live there. Where is all this money going? How much is stolen? Investigate this corrupt mess immediately! — Donald J. Trump (@realDonaldTrump) July 27, 2019

The tweets have prompted reprisals, including from David Axelrod, a senior adviser to President Barack Obama, who said they are "unworthy" of a president and exemplified why Trump might lose his re-election bid in 2020.

Baltimore-born CNN anchor Victor Blackwell teared up as he defended his home district and said Trump's tweets are clearly "about black and brown people."

Cummings, the House Oversight Committee chairman, has been a harsh critic of what he argues is the Trump administration's poor treatment of migrants seeking asylum in the U.S. During a hearing on Thursday, Cummings shouted down acting Secretary of Homeland Security Kevin McAleenan over conditions in migrant camps.

[ALSO READ: Maryland district Trump hate-tweeted a mix of 'The Wire' and upscale suburbia]

Last week, Cummings also gained the authority to subpoena top White House aides for their personal email and text messages, including those of Trump's daughter, Ivanka Trump, and son-in law Jared Kushner, as part of an inquiry into whether there have been any violations of federal record-keeping laws.

Trump's criticism of Cummings' majority-black district comes after the president engaged in a war of words with a group of four liberal minority women lawmakers who call themselves “the squad," Democratic Reps. Alexandria Ocasio-Cortez of New York, Ilhan Omar of Minnesota, Rashida Tlaib of Michigan, and Ayanna Pressley of Massachusetts, insisting that they “go back” to their home countries, although only Omar was born outside of the United States.