The Kakhovka dam and electric plant on the front line in southern Ukraine was destroyed today, sending torrents of water through the breach and forcing tens of thousands of people to evacuate.

Russia and Ukraine were quick to blame each other for the disaster, but it was not immediately clear who was responsible. A deliberate internal explosion was most likely the cause, engineering and munitions experts said. Officials in Kyiv said that Moscow’s forces had blown up the Russian-controlled dam in the predawn hours, a day after U.S. officials said it appeared a Ukrainian counteroffensive had begun.

Residents of Antonivka, a town about 40 miles downstream, described watching in horror as roiling floodwaters carried trees and debris from washed-out houses. More than 40,000 people could be in the path of the flooding in both Ukrainian- and Russian-controlled territory, a Ukrainian official said. (Here’s a map.)

“People here are shocked,” said our colleague Marc Santora, who was in southern Ukraine. “They’ve gotten used to all sorts of Russian bombardment, all sorts of horrors, but this is just so much bigger in both magnitude and the repercussions that it is going to have across society.”

The dam supplies water for drinking, agriculture and cooling reactors and spent fuel at the Zaporizhzhia Nuclear Power Plant. The U.N.’s nuclear watchdog said there was “no immediate nuclear safety risk” at the plant, but that the group was closely monitoring the situation.

The destruction could also dislodge land mines in the region, which will create new hazards as they are washed downstream. Experts were still assessing the full scale of the disaster, and said the flooding was expected to intensify as the waters from the reservoir continue to flow, and then peak in a day or two.

A stunning change in the golf world

For the last year, the PGA Tour and LIV Golf, an insurgent league bankrolled by Saudi Arabia, have been in a bitter rivalry for supremacy in men’s professional golf. Players, fans and sponsors were sharply divided between the classic league and its controversial new rival, which offered tournament prize funds that were the richest in golf history.

Prince Harry’s first day of testimony

At the High Court in London, Prince Harry — the younger son of King Charles III — took the stand today in his lawsuit against the Mirror newspaper group, and accused the company of hacking his cellphone more than a decade ago.

In his striking, sometimes emotional testimony, Harry declared that “some editors and journalists do have blood on their hands” because of the lengths to which Britain’s tabloids often went to gather news about him; his mother, Princess Diana; and other famous figures. His testimony is to continue tomorrow.

The U.S. is cracking down on cryptocurrency firms

The S.E.C. today sued Coinbase, the largest cryptocurrency trading platform in the country, claiming that the company broke securities law by not registering as a broker. The move came just one day after federal regulators sued Binance, the world’s biggest cryptocurrency trading exchange, for mishandling customer funds. The legal actions mark a shift toward enforcement in an industry long characterized by its lack of regulation.

“Regulators have been trying to get their arms around the entire cryptocurrency industry since it was formed more than 10 years ago,” our colleague Emily Flitter said. “It has been even more of a focus since last November,” when the crypto behemoth FTX collapsed.

L.G.B.T.Q. travelers are venturing where being gay isn’t safe

A romantic island getaway in the Maldives. A safari in Kenya. A visit to the pyramids in Egypt.

Apart from being popular, these trips have one thing in common: They are destinations where strict anti-L.G.B.T.Q. legislation is in place, carrying punishments ranging from lashes to imprisonment.

It’s always America for John Mellencamp

In a conversation with The Times, Mellencamp, now 71, reflected on his decades in music and his new album, “Orpheus Descending,” which will be released on June 16. It takes a scornful look at economic disparity, corruption, gun violence and other aspects of life in America, “this land of plenty, where nothing gets done,” as he sings in a track.

It might be fair to say that the rocker, who amassed a catalog of Billboard Top 40 hits, including “Jack and Diane,” and “Pink Houses,” is always singing about America, regardless of the era.

“It’s always the same song,” he said, “just more mature or with a different angle.”

Dinner table topics

WHAT TO DO TONIGHT

“Your mother” has been used as a zinger for centuries

When the Old Testament’s King Saul declared, “Thou son of the perverse rebellious woman,” he was effectively using the ancient version of the well-known “you S.O.B.” Centuries later, Shakespeare used a similar barb in his tragedy “Titus Andronicus.”

Our colleague Deb Amlen unearthed those tidbits, and many more, in her exploration of the history of insults.

She found that, despite the different time periods and languages, the content of insults hasn’t really evolved: They’re still highly personal barbs about people’s status, appearance, sexual prowess and courage (or lack thereof).

Have an old-fashioned evening.

Thanks for reading. We’ll be back tomorrow. — Matthew and Justin

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