JUDY WOODRUFF:

President Trump has expressed growing frustration over what he says is China's reluctance to rein in North Korea.

One soldier from the NATO-led mission in Afghanistan has died in a suicide attack north of Kabul. Five other troops and an interpreter were wounded.

And a sad update to a story we brought you recently. A man who died in an attack in Western Afghanistan this week has been identified as the father of a girl on the country's now famous robotics team. The all-girls team won a silver medal in a U.S. competition last month, after being denied visas to the United States two times.

We will have more on the U.S. involvement in Afghanistan later in the program.

The U.S. Environmental Protection Agency now says that it won't delay rules on reducing carbon emissions. EPA head Scott Pruitt originally said that he'd hold off on enforcing an October 1 deadline for states to start meeting new ozone pollution standards. But after 16 Democratic state attorneys general sued Pruitt over the change, he reversed course.

The Pacific Northwest is enduring one of its most prolonged heat waves in years. The temperature was expected to hit 106 degrees in Portland, Oregon, which would be just shy of a record.

Meanwhile, smoke from wildfires burning in British Columbia, Canada, has snaked into Washington and Oregon, causing breathing problems for people with asthma.

There are new questions about President Trump's plan to hire 15,000 more Border Patrol agents and immigration officers. That's according to a recent report from the Department of Homeland Security's inspector general. It said that officials are — quote — "facing significant challenges in identifying, recruiting, hiring, and fielding the number of law enforcement officers that the president mandated."

Canada, meantime, is making space for hundreds of asylum seekers who have crossed the border from the U.S. in recent weeks. Montreal opened the doors of its Olympic stadium to hundreds of Haitian newcomers to the country, as temporary housing options filled up. In the first half of this year, some 4,300 asylum seekers have arrived in Canada from the U.S. Many are unsure of their status under the Trump administration.

On Wall Street today, the Dow Jones industrial average gained 10 points to close at 22026. The Nasdaq fell 22. And the S&P 500 dropped five.