At least 17 people were shot and killed at Marjory Stoneman Douglas High School in south Florida on Wednesday, authorities said.

Police responded to an incident at the school, located in the city of Parkland, around 3:15 p.m. ET. One shooter is believed to have carried out the attack, in the school's freshman building. The suspect, identified as 19-year-old Nikolas Cruz, was taken into custody "without incident," Broward County Sheriff Scott Israel said. The suspect was a former student of the school who had been expelled; one teacher told The Miami Herald that Cruz had been identified last year as "threatening students."

About 3,000 students attend the school, which is described as being in "an affluent Fort Lauderdale suburb," The New York Times writes.

Drone footage of the scene showed handfuls of students fleeing on foot. "My prayers and condolences to the families of the victims of the terrible Florida shooting," President Trump tweeted. "No child, teacher, or anyone else should ever feel unsafe in an American school." The Week Staff

This is a breaking news story and has been updated throughout.

Singer Andrea Bocelli shared on his Facebook page Tuesday that he and some members of his family tested positive for coronavirus in March, but were "fortunate enough to have a swift and full recovery recovery" by the end of the month.

Bocelli shared that he had a mild case, and waited to tell fans because he did not want to "unnecessarily alarm" them. Bocelli also said he has donated blood to help researchers find a cure. Last week, Bocelli told The Wall Street Journal he had been infected and had a "fever" and "a little bit of a cough."

For Easter on April 12, Bocelli sang alone inside the Duomo in Milan, with his performance livestreamed on YouTube. He set a record for biggest audience to watch a classical livestream, with more than 2.8 million concurrent viewers at one point. Catherine Garcia

Health officials in Missouri and Kansas are calling on people who packed the Lake of the Ozarks over Memorial Day weekend to go into self-quarantine for 14 days.

Lake of the Ozarks is a popular reservoir in central Missouri, and video posted online showed revelers standing shoulder to shoulder in the water, with most not wearing masks. On Monday night, the St. Louis County Department of Health issued an advisory saying anyone who was there and ignored social distancing guidelines should self-isolate for 14 days or until they test negative for coronavirus. On Tuesday, the Kansas Department of Health and Environment made the same recommendation.

"This reckless behavior endangers countless people and risks setting us back substantially from the progress we have made in slowing the spread of COVID-19," St. Louis County Executive Sam Page said in a statement. Missouri Gov. Mike Parson (R) said during a press conference on Tuesday that "poor decisions were made and the social distancing was not followed," which is "potentially dangerous for everyone, especially our most at-risk individuals."

As of Tuesday evening, there are 12,291 confirmed coronavirus cases in Missouri, a 1.3 percent rise over the last 24 hours and an 8.3 percent increase over the last week, ABC News reports. Catherine Garcia

Former Vice President Joe Biden said on Tuesday that President Trump is "supposed to lead by example" when it comes to wearing a mask and social distancing during the coronavirus pandemic, but has failed at both those things and keeping the death toll down.

The United States is close to reaching the grim milestone of 100,000 confirmed coronavirus deaths. During an interview with CNN's Dana Bash, Biden said it is as important as ever to stay safe by social distancing and wearing a face covering, as the COVID-19 threat is "not over."

Biden then appeared to reference a recent report by Columbia University researchers, who found that if federal social distancing measures had been enacted nationwide just one week earlier in March, about 36,000 coronavirus deaths would have been prevented, with even more lives saved if they were released on March 1. The first imported case of COVID-19 in the U.S. was reported on Jan. 20, with community transmission following a few weeks later.

"One hundred thousand deaths and at least 35,000 to 50,000 were avoidable, but for a lack of attention and ego," Biden said. Catherine Garcia

President Trump on Tuesday night accused Twitter of "interfering" in the 2020 presidential election after the company attached a fact check to two of his tweets that made false claims about mail-in ballots.

Trump declared that mail-in ballots are fraudulent, which led Twitter to include links in the tweets redirecting users to a page with facts on the issue. This was the first time Twitter has labeled Trump's tweets as being misleading, and he was quick to respond, claiming that the company is "completely stifling FREE SPEECH, and I, as President, will not allow it to happen!"

Twitter did not delete any of his tweets, despite calls to do so by people directly affected by his messages, nor did the company ban his account. In a statement, a Twitter spokesperson said his tweets "contain potentially misleading information about the voting process and have been labeled to provide additional context." Trump dismissed Twitter's fact checking, saying the research was conducted by "Fake News CNN and the Amazon Washington Post." Catherine Garcia

Twitter on Tuesday labeled two of President Trump's tweets about mail-in ballots as being misleading, the first time the company has tagged false claims he has made on the platform.

The tweets, which incorrectly declared that mail-in ballots are fraudulent, now have labels that say, "Get the facts about mail-in ballots." The links redirect users to a fact-check page with articles about the matter. A Twitter spokesperson said Trump's tweets "contain potentially misleading information about the voting process and have been labeled to provide additional context."

Brad Parscale, Trump's campaign manager, said in a statement his team "always knew that Silicon Valley would pull out all the stops to obstruct and interfere with President Trump getting his message through to voters."

Trump has long faced criticism for spreading falsehoods on Twitter, and over the last few days has used the platform to insult several Democratic lawmakers and spread a conspiracy theory about Lisa Klausutis, a woman who died while working for Joe Scarborough when he was a member of Congress. On Tuesday, Klausutis' widower asked Twitter to delete Trump's tweets, saying he has "struggled to move forward with my life" because of the "barrage of falsehoods, half-truths, innuendo, and conspiracy theories" about his wife's death. Catherine Garcia

Former Vice President Joe Biden on Tuesday fired back at President Trump for sharing a tweet that mocked Biden for wearing a mask during a Memorial Day event, calling him an "absolute fool."

The Centers for Disease Control and Prevention has recommended that people wear masks to slow the spread of coronavirus, but Trump has opted out of publicly wearing a face covering during visits to factories, despite the companies requiring masks for the safety of their employees. This is irresponsible, Biden told CNN's Dana Bash, and Trump's refusal to listen to health experts is "costing people's lives." Presidents, Biden added, "are supposed to lead, not engage in folly and be falsely masculine." Catherine Garcia