Donald Trump

His campaign manager Kellyanne Conway said the mass deportation plan, which was a central plank of his campaign, was yet "to be determined".

Her comments at the weekend came after Mr Trump met with a new panel of Hispanic advisers.

He told Fox News on Monday he was not "flip-flopping" but wanted a fair plan.

"We want to come up with a fair but firm process. Fair but firm," he said, without giving specifics.

There are firings and hirings. Words delivered and then withdrawn or explained away. The politician without regrets tries being sorry.

It can almost be awe-inspiring to watch; the attempted revival of Donald Trump. This was, until very recently, the freewheeling candidate who would not be polished or restrained. That was his badge of authenticity. He had scratched his way to the nomination by not being a politician.

Mr Trump has put his vow to toughen the country's immigration policies at the centre of his campaign.

He has promised to carry out mass deportations and build a wall on the US-Mexico border — proposals that critics have assailed as inhumane and too costly and unrealistic to achieve.

The paper employed a property information firm to search publicly available data on more than 30 US properties connected to the Republican candidate, including offices and golf courses.

In addition to the $US650 million ($852 million) liabilities, "a substantial portion of his wealth is tied up in three passive partnerships that owe an additional $US2 billion to a string of lenders", the newspaper said about debt that could significantly affect Mr Trump's wealth.

Speaking in Dimondale, Michigan -- a predominantlywhite suburb of Lansing -- Trump lamented the collapse of American manufacturing and criticized free trade deals as he laced into Hillary Clinton and the Democratic Party, saying they are taking black voters for granted.

He'd lost his swagger. His mojo was flat.

That was this time last week.

Donald Trump, the Teflon terminator who breezed through the primaries dropping flaming bombs of rhetoric that would have choked any other campaign, was suddenly looking vulnerable.

He loves to cite poll numbers, when they're good, but when they're almost universally bad what is there to talk about?

"This morning Paul Manafort offered, and I accepted, his resignation from the campaign," Mr Trump said in a statement.

"I am very appreciative for his great work in helping to get us where we are today, and in particular his work guiding us through the delegate and convention process.

"Paul is a true professional and I wish him the greatest success."

Trump, reading from prepared remarks on Thursday night, acknowledged that he sometimes says "the wrong thing" in an astonishing act of contrition that signaled Trump's willingness to break from his characteristic brashness and bare-knuckles style that carried him to victory in the Republican primaries, but risks dooming him in the general election.

The killing of Sylville Smith, which took place in a predominantly African-American part of Milwaukee on Saturday, led to several days of protests.

"We have to obey the laws or we don't have a country," Mr Trump told Fox News after visiting police in the city.

A string of fatal police shootings have sparked demonstrations across the US.

Protesters say the police are too ready to use lethal force against African Americans.

In the latest incident on Saturday, 23-year-old Mr Smith was stopped by police and then fled.

The proposal, outlined in a speech in Ohio, includes temporarily suspending visas from countries with terrorist ties as well as introducing an ideological test for those entering the US.

Though Mr Trump has yet to outline which countries would be included on the list, he told supporters at the rally he would "ask the State Department and Department of Homeland security to identify regions where adequate screenings cannot take place".