An exchange of prisoners between Russia and Ukraine from their 3-year-old war was underway Friday, a senior Ukrainian official said, in one of the few signs of progress in international efforts to halt the fighting.

The swap was not yet finished, according to the official, who spoke on condition of anonymity because he was not authorized to speak publicly.

Harvard University is challenging the Trump administration's decision to bar the Ivy League school from enrolling foreign students, calling it unconstitutional retaliation for defying the White House's political demands.

In a lawsuit filed Friday in federal court in Boston, Harvard said the government's action violates the First Amendment and will have an "immediate and devastating effect for Harvard and more than 7,000 visa holders."

Japan's Prime Minister Shigeru Ishiba said Friday that he held telephone talks with U.S. President Donald Trump and agreed to hold "productive" discussions at an upcoming tariff talks between the two sides.

"Investment, not tariffs," Ishiba told reporters after the talks. He said Japan's position to keep pushing Washington to drop all recent tariff measures is unchanged and that he stands by plans to push for Japanese investment to create more jobs in the U.S. in exchange.

Prosecutors in Turkey issued arrest warrants for 63 active-duty military personnel Friday over links to a group accused of attempting a coup in 2016.

Istanbul Chief Public Prosecutor's Office said the suspects included four colonels and came from the army, navy, air force and gendarmerie. Early morning raids across the country resulted in 56 suspects being detained.

Since President Donald Trump announced his intent to end a half-century of U.S. sanctions on Syria, a debate has developed in his administration over how quickly and thoroughly that should happen.

At risk could be the future of a transitional government run by those who drove Syrian leader Bashar Assad from power late last year and hopes that it can stabilize the country after a devastating 13-year civil war that has left millions dead or displaced, the economy in ruins and thousands of foreign fighters still on Syrian soil.

Markets on Wall Street and in Europe declined rapidly early Friday morning after President Donald Trump posted a pair of tariff threats on social media, one aimed at Apple and the other at the European Union.

Futures for the S&P 500 and the Dow Jones Industrial Average slid 1.5% and Nasdaq futures tumbled 1.7% before the bell. Oil prices fell and Treasury yields sank as well.

According to the head of the Palestinian Red Crescent Society, the medic Asaad al-Nsasrah has not spoken with the media since Israeli soldiers killed 15 emergency responders in southern Gaza on March 23.

Words in Hebrew could be heard in the final moments of a video of the killings that was subsequently found and made public.

Iran and the United States began a fifth round of negotiations over Tehran's rapidly advancing nuclear program Friday in Rome, with enrichment emerging as the key issue.

U.S. officials up to President Donald Trump insist Iran cannot continue to enrich uranium at all in any deal that could see sanctions lifted on Tehran's struggling economy. Iran's Foreign Minister Abbas Araghchi early Friday insisted online that no enrichment would mean "we do NOT have a deal."

The man accused of fatally shooting two staff members of the Israeli Embassy in Washington outside a Jewish museum told police after his arrest, "I did it for Palestine, I did it for Gaza," federal authorities said Thursday in announcing charges in the killings they called a targeted act of terrorism.

Elias Rodriguez, 31, shouted "Free Palestine" as he was led away after his arrest, according to charging documents that provided chilling new details of the Wednesday night shootings in the nation's capital that killed an American woman and an Israeli man who had just left an event at the museum. They were set to become engaged.

Prime Minister Nawaf Salam said Israel’s attacks "will not deter the state from its commitment to the electoral process,", after Israel carried out strikes on multiple areas in southern Lebanon on Thursday, some far from the border, only two days before municipal elections are slated to take place in south Lebanon.

Salam called for more international pressure to make Israel stop bombing his country.