Tens of thousands of people march to protest theTrump administration's "zero tolerance" immigration policy, near the Capitol in Washington, D.C. United States, on June 30, 2018. (Xinhua/Yang Chenglin)

WASHINGTON, June 30 (Xinhua) -- From coast to coast, in the rain or under the burning sun, tens of thousands of Americans marched and rallied across the country to protest the Trump administration's "zero tolerance" immigration policy resulting in over 2,000 children separated from their families who crossed the border illegally.

It's very hot in downtown Washington D.C. on Saturday, but that hasn't stopped thousands of protesters pouring into Lafayette Square facing the northern side of the White House.

They chanted "We care," "keep families together" and other slogans slamming U.S. President Donald Trump's tough immigration policy.

In Boston, Democratic Senator Elizabeth Warren told a rally that "Mothers have told me that at night, they believe they can still hear their children cry. This is not about politics. This is about human beings."

In the state of New Jersey, several hundred people gathered along a road a few miles away Trump's National Gold Course, where the president and his family are spending the weekend.

Protesters were holding signs with the messages, "Even the Trump family belongs together" and "Do you know where our children are?"

A protester holds a poster during protest against the Trump administration's "zero tolerance" immigration policy, near the White House in Washington, D.C. United States on June 30, 2018. (Xinhua/Yang Chenglin)

Organizers said about 630 Families Belong Together events had been planned across the whole country with Washington D.C. as the main protest venue, calling the rallies a forum for people to stand up to the president's controversial immigration policies.

"(The) family separation crisis is not over. We have a situation where the Trump administration seems to be aiming to detain families," said Karthik Ganapathy, a MoveOn.org spokesman.

The Trump administration's "zero-tolerance" policy dictates that all immigrants arriving U.S. shores illegally should be handed in for prosecution and detained under federal custody, and that children traveling with their parents will be sent separately to the U.S. Health and Human Services Department, where they are supervised by other family members, provided with shelters, or sent to foster homes.

As a result of the hardline policy, pictures of distraught children separated from their families were widely circulated, sparking domestic and global outrage.

Facing domestic and international backlash, Trump signed an executive order on June 20 reversing his policy of separating families, and replacing it with a policy of detaining entire families together, including children, but ignoring legal time limits on the detention of minors.

The Trump administration announced on Friday that it will now hold families together for longer than 20 days.

According to government figures, more than 2,300 minors were separated from their families after illegally crossing the U.S. southern border with Mexico from May 5 through June 9.