These people are living in hellHe told NBC's Meet the Press in his first broadcast network interview since winning November's election.
The Republican also vowed to end automatic citizenship for anyone born in the country but offered to work with Democrats to help some undocumented immigrants who were brought to the US as children.
In the wide-ranging sit-down, which was recorded on Friday, Trump promised to issue "a lot" of executive orders, including on immigration, energy and the economy, after he is inaugurated on 20 January.
While he suggested he would not seek a justice department investigation into Joe Biden, he said that some of his political adversaries, including lawmakers who investigated the Capitol riot, should be jailed.
Trump was asked whether he would seek to pardon the hundreds of people convicted of involvement in that riot, when supporters of his stormed Congress three months after his defeat in the 2020 election.
We're going to look at independent casesHe said. "Yeah, but I'm going to be acting very quickly."
First dayHe added.
Trump continued:
You know, by the way, they've been in there for years, and they're in a filthy, disgusting place that shouldn't even be allowed to be open.
The president-elect made other news in the NBC interview aired on Sunday:
He offered a caveat on whether he would keep the US in the North Atlantic Treaty Organization (Nato): "If they're paying their bills, and if I think they're doing a fair - they're treating us fairly, the answer is absolutely, I'd stay with Nato"
Trump said he would not seek to impose restrictions on abortion pills, though when asked to make a guarantee, he added:
Well, I commit. I mean... things change
The Republican said Ukraine should "probably" expect less aid when he returns to the White House
Trump said he thinks "somebody has to find out" if there is a link between autism and childhood vaccines - an idea that has been ruled out by multiple studies around the world. Trump suggested his nominee for health secretary, vaccine sceptic Robert F Kennedy Jr, would look into the matter.
The president-elect repeated his promise that he will not seek to cut Social Security, nor raise its eligibility age, though he said he would make it "more efficient", without offering further details
Pressed on whether his plan to impose tariffs on imports from major US trading partners would raise consumer prices for Americans, he said: "I can't guarantee anything. I can't guarantee tomorrow"
On the subject of immigration, Trump told NBC he would seek through executive action to end so-called birthright citizenship, which entitles anyone born in the US to an American passport, even if their parents were born elsewhere.
Birthright citizenship stems from the 14th Amendment of the US Constitution, which states that "all persons born" in the United States "are citizens of the United States".
We're going to have to get it changed," Trump said. "We'll maybe have to go back to the people. But we have to end it.
Trump also said he would follow through on his campaign pledge to deport undocumented immigrants, including those with family members who are US citizens.
I don't want to be breaking up familiesHe said, "so the only way you don't break up the family is you keep them together and you have to send them all back."
Trump also said he wants to work with Congress to help so-called Dreamers, undocumented immigrants who were shielded under an Obama-era programme, Deferred Action for Childhood Arrivals, which Trump once attempted to scrap.
I will work with the Democrats on a planHe said, adding that some of these immigrants have found good jobs and started businesses.
Trump seemed to offer mixed signals on whether he would follow through on his repeated vows to seek retribution against political adversaries.
Outgoing US President Joe Biden this week issued a sweeping pardon to his criminally convicted son, Hunter. The Democrat is reported to be considering other blanket pardons for political allies before he leaves office next month.
Trump seemed to indicate that he would not seek a special counsel investigation into Biden and his family, as he once vowed.
I'm not looking to go back into the past," he said. "I'm looking to make our country successful. Retribution will be through success.
But he also said that members of the now-defunct, Democratic-led House of Representatives committee that investigated him
should go to jail
One member of the panel, former Republican congresswoman Liz Cheney, hit back at Trump on Sunday.
She said his comment that members of the committee should be jailed was a "continuation of his assault on the rule of law and the foundations of our republic".
In his NBC interview Trump also said he would not direct the FBI to pursue investigations against his foes.
But he also told the network: "If they were crooked, if they did something wrong, if they have broken the law, probably.
They went after me. You know, they went after me, and I did nothing wrong.
