Howard Berkes

Updated at 4:50 p.m. ET

Investigators in Las Vegas are sifting through evidence they've gathered from the homes of the man who sprayed a concert crowd with gunfire. They've begun to interview his girlfriend. They've learned quite a bit about Stephen Paddock's past and preparation, but there is still no explanation for why he damaged and destroyed so many lives.

The second-highest ranking member of the Florida Senate pledged a legislative review of a state law that has allowed injured undocumented workers to be arrested and potentially deported rather than paid workers' compensation benefits.

"Legitimate injuries shouldn't be denied just because the person was an undocumented immigrant," said Republican Sen. Anitere Flores, the president pro tempore of the state Senate and chairwoman of the Banking and Insurance Committee.

NPR's ongoing investigation of the advanced stage of the fatal lung disease that afflicts coal miners has identified an additional 1,000 cases in Appalachia.

That brings the NPR count of progressive massive fibrosis, the most serious stage of the disease known as black lung, to nearly 2,000 cases in the region, all of which were diagnosed since 2010.

Across Appalachia, coal miners are suffering from the most serious form of the deadly mining disease black lung in numbers more than 10 times what federal regulators report, an NPR investigation has found.

The government, through the National Institute for Occupational Safety and Health, reported 99 cases of "complicated" black lung, or progressive massive fibrosis, throughout the country the last five years.

West Virginia's Democratic candidate for governor is a billionaire, a philanthropist and a resort and coal mine owner who cites his business and mining experience as major attributes as he seeks to lead his home state out of a severe budget and economic crisis.

"I am not a career politician; I am a career businessman," wrote Jim Justice in an April 5 op-ed that appeared in the Charleston Gazette-Mail.

An Oklahoma law that lets employers opt out of state-regulated workers' compensation has been rejected and declared unconstitutional by state regulators.

The Oklahoma Workers' Compensation Commission called the alternative workplace-benefit plans that some employers adopted under the law "a water mirage on the highway that disappears upon closer inspection."

The unanimous ruling by the commission, issued Friday, is expected to be appealed.

Thirty years ago, as the nation mourned the loss of seven astronauts on the space shuttle Challenger, Bob Ebeling was steeped in his own deep grief.

The night before the launch, Ebeling and four other engineers at NASA contractor Morton Thiokol had tried to stop the launch. Their managers and NASA overruled them.

That night, he told his wife, Darlene, "It's going to blow up."

Kevin Schiller had no idea what hit him.

With 21 years on the job, the building engineer for Macy's department stores had been in and out of every nook and cranny of many of the retail giant's Texas stores, including the storage room in the Macy's in Denton, Texas.

One minute, the stocky, 6-foot-2 Schiller was searching there for a floor drain. The next, he was sprawled on the floor, stunned, confused and bleeding slightly.

Billy Doyle Walker loved working in the sky. He used to say he could see forever, perched high up communications towers as he applied fresh paint.

Three years ago, working halfway up a 300-foot steel tower at the LBJ Ranch, the panoramic view included the rolling green hills and meadows of the Texas Hill Country. The tower was used by former President Lyndon B. Johnson to communicate with the White House.

The nation's coal miners have lost an advocate — a pulmonologist who helped create a national movement in the 1960's that focused national attention on the deadly coal miners' disease known as black lung.

Dr. Donald Rasmussen died July 23 at age 87 in Beckley, W.V., where he spent close to 50 years assessing, studying and treating coal miners — more than 40,000 of them, by his account. His work documenting the occurrence of black lung helped trigger a statewide miners strike in West Virginia in 1969.

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