GEOFF BENNETT: Welcome to the "News Hour."

Russia today freed an American imprisoned for the last four years.

Stephen Hubbard was captured in Eastern Ukraine and was convicted of fighting against Russia.

AMNA NAWAZ: The 74-year-old retired teacher from Michigan was reportedly freed without a swap deal.

U.S.

special envoy Steve Witkoff greeted Hubbard in St.

Petersburg.

He also met with Russian President Vladimir Putin and praised Putin in unusually glowing terms.

Nick Schifrin begins our coverage.

MAN: Mr.

Steve Witkoff.

NICK SCHIFRIN: In St.

Petersburg today, filmed by Russian state TV, President Trump's top envoy freeing a detained American.

Ambassador Steve Witkoff embraced Stephen Hubbard, imprisoned for four years and facing another nearly five years of detention in a justice system overseen by one man whom Witkoff personally thanked.

STEVE WITKOFF, U.S.

Special Envoy to the Middle East: We just left President Putin.

He sends you blessings and wishes you good things.

STEPHEN HUBBARD, Released American Prisoner: OK.

Really?

He does?

NICK SCHIFRIN: Tonight, the 74-year-old Hubbard is flying home to the U.S.

for evaluation, and a U.S.

official tells "PBS News Hour" he's in OK condition.

Hubbard's a retired schoolteacher from Michigan who moved to Ukraine with his wife in 2014.

He was captured four years ago by Russian troops as they took over parts of Eastern Ukraine.

And then he was convicted by a Moscow court, where the conviction rate is over 99 percent, for being a -- quote -- "Ukrainian mercenary."

And multiple U.S.

officials say, unlike previous Russian detainee releases, like Brittney Griner, who was swapped for convicted arms dealer Viktor Bout, Hubbard was released without a swap.

STEVE WITKOFF: So good to see you.

VLADIMIR PUTIN, Russian President: Hello.

NICK SCHIFRIN: Ahead of the release, Witkoff greeted Putin.

STEVE WITKOFF: Thank you for having us.

NICK SCHIFRIN: And the two lavished mutual praise, even if Putin is an accused war criminal indicted by the International Criminal Court.

VLADIMIR PUTIN (through translator): I know that President Trump pays special attention to this matter, primarily for humanitarian reasons.

STEVE WITKOFF: You talk so much about my president, President Trump, being a humanitarian.

You are a humanitarian also, sir.

And I salute that.

I commend you, and I thank you again.

NICK SCHIFRIN: European officials worry Witkoff and the Trump administration consider Putin a partner in peace and business, something Putin today made explicit.

VLADIMIR PUTIN (through translator): Both sides would be interested in discussing issues related to our plans to restore bilateral relations, including in the area of economic cooperation.

NICK SCHIFRIN: It was Putin who launched the full-scale invasion of Ukraine.

And, today, he agreed to relaunch a U.S.

Russia-Ukraine diplomatic track that last met in February and helped produce releases of prisoners of war.

Today, Ukrainian President Volodymyr Zelenskyy agreed, although he prefers a leaders-level summit.

VOLODYMYR ZELENSKYY, Ukrainian President: It's important to negotiate trilaterally.

I think this is the best way President Trump, with his leadership, and me and Russian leader, trilaterally, better with Europeans, but minimum trilaterally, I think so.

This is important.

NICK SCHIFRIN: And yet the war grinds on in Russia's battlefield of choice, Ukrainian cities.

Today, a drone carved through Kiev apartments, killing two people.