Law enforcement officials gather outside Pulse nightclub, the scene of the June 12 mass shooting in Orlando, Fla. Credit: David Goldman/Associated Press

We’re continuing to compile essential coverage of Sunday’s massacre in Orlando, Florida, and its repercussions. We’ll continue to collect the best work explaining the worst mass shooting in U.S. history. If you have something you think we should include, tweet us @reveal or find us on Facebook.

The investigation

The New York Times looks at the FBI’s earlier investigation into shooter Omar Mateen.

“I think the F.B.I. has an incredibly hard job, because this guy seems like a lone wolf,” said Caroline Fredrickson, the president of the American Constitution Society, a frequent critic of the agency. “He was an American citizen born in the United States. Law enforcement has been working its butt off to figure out what else could be done.”

The shooter’s wife reportedly knew about his plot, according to The Huffington Post.

She had driven him to Pulse nightclub on an earlier occasion when he scouted the location, according to NBC. CBS News said that she had also traveled with him to Disney World in April as he allegedly surveilled parts of the amusement park and that she went with him to downtown Orlando earlier this month to scout other Disney facilities as well as the nightclub.

A survivor of the attack says that during the attack, Mateen told them that he “didn’t have a problem with black people.”

He asked the people in the stalls if there were “any black people” in the bathroom. A man next to Carter said there were “six or seven of us.” Mateen responded that he “didn’t have a problem with black people,” Carter said. “He said, ‘You guys have suffered enough’ ” at the hands of white Americans.

Caring for the survivors

Medical staff look for ways to improve trauma care during mass shootings, from The New York Times.

Specialists in emergency medicine say the escalating severity of mass shootings in the United States calls for a re-evaluation of the medical response. In the past, disaster drills have focused on crises like bus accidents or plane crashes, which involve blunt trauma injuries, not gunshots from high-powered weapons capable of mowing down dozens of people at a time.

Fusion looks at the additional burden on undocumented families in the aftermath of the Orlando shootings.

“For many families, no matter how much money they raise they still may not be able to get permission to come to the U.S.,” said Ramirez. “For the family to be watching this back in their countries and not be able to help their sons is painful; this all hurts the family back home too.”

Making sense of the horror

The Washington Post features memories of those killed in the attack.

Solivan, who went by Mary and was from Ponce, Puerto Rico, was married and had two young boys. Her Facebook page is a series of photos of someone who loves family life – her two children horsing around among pillows, her eldest son and husband wearing matching wacky T-shirts, that same son in a Captain America costume.

The Huffington Post asks how to move forward if Mateen was, indeed, gay.

To put it more plainly: the things that we hate the most about others are often the things that we hate the most about ourselves and that hate can bring disastrous consequences. This isn’t any kind of brilliantly new or incandescent truth — it’s one of the oldest, saddest stories in the raggedy book that houses our shared human history. But perhaps merely being reminded of it can offer us a way to begin to reimagine ourselves and our culture in what feels like the endless (and endlessly suffocating) dusk of Sunday’s massacre.

BuzzFeed compiled reflections from the LGBT community on queer bars as places of security.

I was 17 years old in 1979 when my gay boyfriend and I ventured to the Parliament House in Orlando, Florida. It was like walking into Wonderland — an alternate Universe I never knew existed. For once, being a fat girl didn’t make any difference. I was embraced and accepted for all that I was. I found myself in the midst of brilliant, eccentric, artistic and whirling-twirling misfits that pulled me into the middle of their all-male fold.

The gun debate

Donald Trump shifts position on gun purchases by those on watch lists.

Presumptive Republican presidential nominee Donald Trump tweeted Wednesday he will meet with the National Rifle Association about not allowing people on a terrorist watch list to purchase guns.

Attorney General Loretta Lynch calls for a new discussions on gun laws.

“We need to have the hard discussion and talk about gun laws that allow an individual to legally purchase weapons that facilitate mass killing. We have to have those hard discussions,” Lynch said at a White House conference on women’s issues.

Focusing on the AR-15 as the main target of gun control misses a larger point, from The Washington Post

While aesthetically similar to and just as lethal as an AR-15, the MCX is internally a different beast, thus all but removing it from the AR-15 family of rifles. Yet while the weapon is different, the MCX and the AR-15 share the same design purpose: providing a highly portable, customizable, easy to operate and accurate rifle for the individual who possesses it.

Defining terror

Foreign Policy asks if there are any more “lone wolf” attackers in an age of ISIS.

Calling Mateen a “lone wolf” risks obscuring more than it reveals, according to Michael Smith, a counterterrorism expert and consultant, because it fails to accurately describe the threat posed by the Islamic State, and masks the relationship the group is building with its sympathizers abroad.

ISIS supporters call for further attacks on the West.

The FBI confirmed in a press conference on Monday that Mateen pledged allegiance to ISIS in a phone call to police before the attack, but investigations and reports into his true motivations continue to emerge. No evidence has emerged to suggest that ISIS directed the attack. Similarly, the new video is also decentralized, not put together by an official ISIS propaganda outfit.

Sam Ward is a senior digital producer for Reveal, where he oversees the web team. He has years of experience producing creative digital media projects for Oregon Public Broadcasting, PBS, ITVS and the Smithsonian, and he has managed projects for funders such as the National Science Foundation, U.S. Department of Education and Annenberg Media. He graduated from Carnegie Mellon University in Pittsburgh. Ward is based in Reveal's Emeryville, California, office.