From Washington, this is VOA news. I'm David DeForest reporting.

Turkey says the three suicide bombers who carried out Tuesday's attack on an Istanbul airport were from Russia, Uzbekistan and Kyrgyzstan.

Turkish officials continue to believe the attack was launched by Islamic State fighters. The death toll from the blasts at Europe's third busiest airport has increased to 44.

The process of replacing British Prime Minister David Cameron started in earnest Thursday. Candidates for leader of the ruling Conservative Party in Britain outlined their strategies for dealing with the consequences of last week's Brexit referendum.

Brexit's supporter Boris Johnson, the flamboyant former mayor of London, has pulled out of the contest. That leaves Interior Minister Theresa May as the favorite to replace Mr. Cameron.

"Following last week's referendum, our country needs strong, proven leadership to steer us through this period of economic and political uncertainty, and to negotiate the best possible terms as we leave the European Union."

There are five candidates competing for the position.

A teenage Palestinian man entered a Jewish settlement in the West Bank Thursday and killed a 13-year-old Israeli-American girl.

Hallel Yaffa Ariel became the youngest victim in the current wave of Palestinian violence against Israelis.

Security guards arrived on the scene and killed the attacker.

The United Nations children's agency says one in five children in Iraq are now at serious risk of death, injury, sexual violence, abduction or forced recruitment into armed groups.

According to the latest UNICEF report, in the past two and a half years, an average of 50 children per month have been abducted or sexually abused.

This is VOA news.

Officials said Thursday airstrikes on about 40 vehicles have killed at least 250 Islamic State fighters in Iraq.

The vehicles were located just south of newly liberated Fallujah.

The commander of U.S. naval forces in the Middle East says the detention of 10 U.S. sailors by the Iranian Revolutionary Guard earlier this year was, in his words, "wholly preventable."

In Navy documents released Thursday, U.S. Navy Vice Admiral Kevin Donegan said the January incident was due to poor leadership, a "non-existent" compliance with proper maintenance and procedures and insufficient planning.

Vice Admiral Chris Aquilino, the deputy chief of Naval Operations, briefed reporters on the matter. "Under command and control, the investigation found a lack of leadership, a disregard for risk management processes and proper mission planning standards. One important note that the investigation stated was that if the guidance provided by the 5th Fleet commander had been followed, this event could have been prevented."

Chief of Naval Operations Admiral John Richardson told reporters at the Pentagon that the Iranian Revolutionary Guard was also at fault.

The United States Thursday added eight countries to its blacklist of nations not doing enough to end human trafficking.

The U.S. State Department has put Uzbekistan and Turkmenistan on the list of its 27 worst offenders along with Myanmar, Haiti, Djibouti, Papua New Guinea, Sudan and Suriname.

Secretary of State John Kerry released the reports.

"And in addition to the rankings, the report outlines our specific concerns as well as the ways we can improve our efforts. This is not meant to be a dunning report; it is meant to be a demarcation, an encouragement process, a process of evaluation and work towards changing rankings."

Kuwait and Thailand were moved off the list of the lowest ranking nations.

Rodrigo Duterte has officially been sworn in as the 16th president of the Philippines in a low-key inauguration in the capital.

Duterte did not take the oath of office in an elaborate public rally. He has frequently denounced the lavish lifestyle associated with the office, saying he will be traveling in an pickup truck rather than the presidential limousine.

Duterte has promised to cleanse the country of criminals in his first six months in office. Though many citizens welcome that action, human rights activists were worrying about potential sweeps of arrests, killings and human rights violations.

On Wall Street, U.S. stock indexes were up at the close of trade today.

In Washington, I'm David DeForest.

That's the latest world news from VOA.