With Clinton grounded, Trump under harsh spotlight

With Hillary Clinton out of action, her White House rival Donald Trump was squarely in the spotlight Wednesday -- but for the wrong reasons, facing scrutiny over his foundation and branded a "disgrace" by the former top diplomat Colin Powell.

The Democratic nominee is expected back on the campaign trail on Thursday after a weekend health scare that grounded her for three days, right as her showdown with Republican Trump enters its final two-month stretch.

But while Clinton's troubles initially provided Team Trump with a golden chance to undermine her, their champion was facing some sharp attacks of his own.

Democratic presidential nominee Hillary Clinton was forced to leave a 9/11 memorial event in New York ©Brendan Smialowski (AFP)

In leaked emails posted on website DC Leaks, Powell blasted Trump as "a national disgrace and an international pariah," a stinging attack on the brash billionaire from a cabinet member in the last Republican administration.

"He appeals to the worst angels of the GOP nature and poor white folks," the retired four-star general, who twice endorsed the Democrat Barack Obama for president, wrote in a separate email.

Powell, who was US secretary of state from 2001 to 2005, confirmed to NBC the hacked messages were authentic.

At the same time, New York state's top law enforcement official said he has opened an investigation into the Donald J Trump Foundation, citing worries the charity has been involved in "impropriety."

The Trump Foundation has faced a series of damaging stories, including reports that it made an illegal $25,000 donation to a campaign group supporting Florida Attorney General Pam Bondi in 2013, just as she was considering joining a fraud case against the Trump University real estate program.

"We have been concerned that the Trump Foundation has engaged in impropriety from that point of view," Attorney General Eric Schneiderman told CNN Tuesday.

Schneiderman has been at loggerheads with Manhattan mogul for years over Trump University, which he calls "straight up fraud."

Trump's campaign pushed back, with spokesman Jason Miller branding Schneiderman "a partisan hack" whose probe "is nothing more than a left-wing hit job designed to distract from Crooked Hillary Clinton's disastrous week."

Trump has weathered waves of attacks over the excesses of his 15-month campaign for the White House. It is unclear how the latest criticism and investigation will impact the race.

But the presidential battle is in the home stretch, with just 12 days until the first Clinton-Trump debate, expected to be the most watched moment of the bruising campaign to date.

- Test results on air? -

Clinton meanwhile was at home in Chappaqua, New York for a third straight day, recovering from pneumonia in a health scare that rocked her bid to become America's first woman president.

She was forced to leave a 9/11 memorial event in New York on Sunday and was seen stumbling limp-legged into a Secret Service vehicle. Clinton's campaign initially said she had been suffering the ill effects of dehydration and "overheating."

Clinton's personal physician later disclosed she had been diagnosed with pneumonia on Friday, two days before the 9/11 event, raising broader questions about her campaign's transparency.

Trump, meanwhile, was reportedly due to disclose details of a recent medical exam in an appearance on medical talk show Dr. Oz set to air on Thursday.

According to the New York Times, Trump handed the celebrity doctor a summary of test results to read out air, during taping of the show on Wednesday.

Clinton will be under renewed pressure to disclose more health information as she returns to the trail Thursday with appearances in Greensboro, North Carolina and then Washington.

Next week she dons her diplomatic cap, holding several bilateral meetings on the sidelines of the UN General Assembly including with Egyptian President Abdel Fattah al-Sisi and Ukrainian President Petro Poroshenko, her campaign said.

Clinton has been under fire for provocative comments she made Friday when she described half of Trump's supporters as being in "a basket of deplorables" because of their racism, misogyny and xenophobia.

Supporters -- including Obama -- have complained that she is being held to a higher standard than her Republican rival, whose campaign has been punctuated by outrageous outbursts.

Nate Silver, a respected election analyst at FiveThirtyEight.com, weighed in on Wednesday, arguing that while both candidates face similar, substantial media scrutiny, Trump's "scandalousness" was 10 times that of rival Clinton.

"There's everything: corruption, racism, lying, fitness for office. Like nothing we've ever seen before," Silver tweeted.

"Trump gets harsh coverage. But it can't, or doesn't, fully scale up to his candidacy."

After an extremely rough few days for Hillary Clinton, US President Barack Obama used a fiery appearance before a crowd in Philadelphia to try to turn the tables on Donald Trump ©Saul Loeb (AFP)

A sign along a road near the home of US Democratic presidential candidate Hillary Clinton wishes her well after she fell ill at a 9/11 memorial ceremony and her doctor later revealed she was diagnosed with pneumonia ©Don Emmert (AFP)

Donald Trump, known for his relentless and personal attacks, brushed off questions from reporters about Hillary Clinton's health on Sunday

US presidential vote ©Philippe Mouche, François D'Astier (AFP)