Washington, D.C., Mayor Muriel Bowser has imposed a two-day nighttime curfew that began at 7 p.m. Monday—but there's an exception for voting in Tuesday's primary.

Vote centers are scheduled to open from 7 a.m. to 8 p.m. ET. The curfew won't apply to anyone out to cast their ballot, poll workers, or essential workers, the mayor said.

The curfew was implemented following unrest sparked by the death of a black man, George Floyd, in policy custody in Minneapolis last week.

Washington, D.C., has encouraged voting by mail because of the coronavirus pandemic, as have the seven states that also have presidential primaries Tuesday.

The district is opening some in-person voting sites, but fewer than usual and with social-distancing measures. It is requiring masks to enter vote centers, and election workers will provide them if necessary, the D.C. Board of Elections said.

In addition to the presidential contest, there are several other races on the ballot, including four seats on the D.C. Council.

Joe Biden is accusing President Trump of failing to act decisively to protect the nation’s economy from the coronavirus pandemic and allowing corruption to seep into the $2 trillion stimulus package.

Mr. Biden on Monday began airing a digital ad in six battleground states that offers a timeline of the pandemic’s spread, saying the president “didn’t build a great economy. His failure to lead destroyed one.”

Mr. Biden’s campaign told The Wall Street Journal that if elected, the former vice president would appoint an inspector general on his first day in office to conduct a retrospective, top-to-bottom review for potential malfeasance of every stimulus loan provided under the CARES Act.

“Any dollar that goes to someone who does not merit it under the law, any dollar taken corruptly, we will find it, we will come get it and we will punish the wrongdoers,” Mr. Biden said in a video released Monday.

Erin Perrine, a spokeswoman for the president’s re-election campaign, called the ad “another absurd and factually inaccurate attempt to be relevant” by Mr. Biden. She said “tens of millions of jobs and businesses in America were protected by President Trump’s work to establish and fund the Paycheck Protection Program.”

Mr. Biden, the likely Democratic presidential nominee, has seized on the president’s response to the outbreak and expressed doubt over the administration’s commitment to ensuring that stimulus funds reach struggling workers and small businesses.

Mr. Biden said in an interview Tuesday with ABC’s “Good Morning America,” that the president has been “incompetent” in his handling of the virus.

The former vice president said his political standing had not been hurt by being forced to remain at his Delaware home. “We're winning if you look at all the polling data,” he said.

The digital ad will appear on Facebook, YouTube and Instagram in Arizona, Florida, Michigan, North Carolina, Pennsylvania, and Wisconsin. Mr. Biden said Monday night at a fundraiser that he was preparing “a detailed plan for the right kind of economic recovery.”

As vice president, Mr. Biden oversaw the nearly $800 billion economic recovery in 2009 and has made the Covid-19 stimulus a central message against Mr. Trump, saying the funds have helped politically connected allies of the president at the expense of small business.

Mr. Biden and Democrats have also pressed for greater oversight, railing against Mr. Trump’s decision to sideline the Pentagon’s acting inspector general, Glenn Fine, who had been set to oversee the new Pandemic Response Accountability Committee.

In the video Mr. Biden said he would empower his inspector general to refer any potential criminal activity to the Justice Department, calling his plan a warning “to anyone who participates in the corrupt giveaways of President Trump and his administration.”

Last week, the White House lawyer tapped to oversee a part of the broader CARES Act said he would act independently from the Trump administration.

Brian D. Miller was nominated by the president to serve as special inspector general for the coronavirus pandemic recovery, or SIGPR, with responsibility for monitoring the Treasury Department’s use of $500 billion to help businesses.

President Trump’s campaign is sinking millions into a new advertising push targeting presumptive Democratic presidential nominee Joe Biden.

A campaign official said the eight-figure ad buy, worth more than $10 million, would include a mix of ads on national cable TV and broadcast channels, as well as online. The plans were first reported by Politico.

The newly aggressive effort against the former vice president has been approved by the president, the official said. The campaign is turning its attention to driving up Mr. Biden’s negative ratings as Mr. Trump faces declining poll numbers.

Campaign manager Brad Parscale previewed the strategy Thursday on Twitter, saying that “in a few days we start pressing FIRE for the first time.”

Mr. Parscale later tweeted an ad that accused Mr. Biden of being soft on China. It features a clip of Mr. Biden last year saying: “China is going to eat our lunch? Come on, man,” and shows text saying: “Biden stands up for China....While China tries to cripple America.”

The two campaigns have been fighting over China, with the president’s allies arguing Mr. Biden has been too accommodating and Mr. Biden’s aides claiming Mr. Trump failed to hold Chinese leaders accountable over the coronavirus pandemic, which originated in China.

Biden spokesman Andrew Bates said in a statement that Mr. Biden pushed the president to act early against the virus while “publicly warning him not to trust the Chinese government's word about containment.” He said that Mr. Trump instead “echoed Chinese Communist Party propaganda and horrifically mismanaged the worst public health crisis in over 100 years.”

Massachusetts Sen. Elizabeth Warren said Thursday that her oldest brother, Don Reed Herring, has died after contracting the coronavirus.

“I’m grateful to the nurses and frontline staff who took care of him, but it’s hard to know that there was no family to hold his hand or to say ‘I love you’ one more time—and no funeral for those of us who loved him to hold each other close. I'll miss you dearly my brother,” Ms. Warren wrote in a series of tweets about her brother.

The former Democratic presidential candidate frequently mentioned her three older brothers who lived in Oklahoma, where the senator was born, during her campaign.

Since suspending her campaign in early March, Ms. Warren has been a vocal critic of the Trump administration's response to the coronavirus and has rolled out her own plans to address the crisis.

Mr. Herring's death was first reported by the Boston Globe.

In a possible early sign of downsizing ahead for this summer’s Democratic National Convention in Milwaukee, the host committee for the gathering is cutting its staff by more than half as it deals with the financial and logistical challenges associated with the coronavirus pandemic.

The Milwaukee 2020 Host Committee, the nonprofit charged with raising $70 million for the event, said Thursday that it will cut its staff from 31 to 14 employees.

“The entire nation is facing the unprecedented challenge of responding to the coronavirus pandemic, and unfortunately, the Milwaukee 2020 Host Committee is no different,” Raquel Filmanowicz, the committee’s chief executive, said in a statement. “In this climate of uncertainty, we must adjust our plans to match the new reality we’re facing as a nation.”

Eleven staffers have been offered positions with either the Democratic National Convention Committee or as organizers for the party, while six have been laid off. Separate from the host committee, the DNCC is the organization responsible for conducting the convention.

The Democratic National Committee said earlier this month that it would push the convention later into the summer because of the pandemic in a move that marked the biggest tangible disruption yet to the presidential campaign as a result of the crisis.

The gathering will now take place the week of Aug. 17, more than a month later than originally planned. That will also delay when the party’s nominee can start using general election dollars to directly confront President Trump.

Officials have said they haven’t made any determination yet on the length or format of the convention, given the outbreak's unpredictability. DNC members have said there’s growing speculation the event is unlikely to host the 50,000 delegates, donors, members of the media and others that were originally expected.

Former Vice President Joe Biden, the party’s presumptive nominee and someone who will have considerable input on convention decisions, has said the event may have to be held in a virtual manner if the virus continues to pose a public health threat in August. Convention organizers are planning for that possibility, as well as other scenarios.

Mr. Trump has said the Republican National Convention will go on as planned in Charlotte, N.C. That gathering, the week after the Democratic gathering, would typically also attract about 50,000 people.