From Washington, this is VOA news. I'm David Byrd reporting. The first full day of Olympic competition got under way Saturday in Rio de Janeiro, with an American teenager winning the first gold.

Shooter Ginny Thrasher won the women's 10-meter air rifle event, edging two Chinese athletes to take the gold.

A little bit later, Hoàng Xuan Vinh gave Vietnam its first ever Olympic gold medal by winning the 10-meter air pistol.

Belgian cyclist Greg Van Avermaet won the gold in the men's cycling road race.

South Korea defeated the United States to take the title in the men's team archery event.

Gold medals were also handed out in men's and women's judo and in fencing.

President Obama used his weekly media address to celebrate the beginning of the Olympics and to call for all Americans to get behind team U.S.A. in Rio.

Mr. Obama said that the Olympic team serves as an example of unity in diversity and comradery in competition.

"It's about the character it takes to train your heart out, even when no one's watching. Just hard work, focus, and a dream. That's the Olympic spirit -- and it's the American spirit, too."

The president called on Americans to cherish the opportunities to come together around one flag despite political differences. He called on the country to enjoy the peaceful competition and sportsmanship in a time of challenges worldwide.

Mr. Obama also praised members of the first ever refugee team as personifying endurance.

The Obama's left Washington Saturday and will spend the next two weeks in Martha's Vineyard in the family's last vacation of Mr. Obama's presidency.

For more on these stories, visit our website. This is VOA news.

Syrian rebel groups say they have broken through areas around the northern city of Aleppo after fierce fighting since July 31.

The British-based Syrian Observatory for Human Rights reports that fighters of Jaish al-Fatah and the rest of the rebel and Islamic factions advanced and met with rebels inside Aleppo.

On Twitter, the powerful ultraconservative Ahrar al-Sham group said on its account that rebels had seized control of Ramousah on the southern edges of the city and had "opened the route to Aleppo."

However, sources close to Syrian government forces denied that they had been pushed out.

Meanwhile, earlier reports Saturday said that a coalition of Arab and Kurdish fighters had taken "almost complete control" of the strategic northern city of Manbij that had been a stronghold of the Islamic State group.

Belgian police say a man carrying a machete and yelling "Allahu Akbar" was shot and killed Saturday shortly after he injured two female police officers in the city of Charleroi.

The attacker was [killed by a third officer and later died] or was shot by a third officer and later died at the hospital.

Belgian Prime Minister Charles Michel said he was closely monitoring the situation. He said, "Our first thoughts are with the police, with the victims. This is a new drama. I will be back in Brussels Sunday and will immediately go to meet security forces in the morning."

The Charleroi attack came after 32 people died in March during coordinated bombing attacks on the Brussels airport and a subway station. Islamic State militants claimed responsibility for those attacks.

South African President Jacob Zuma has acknowledged the country's local elections were hotly contested as his governing African National Congress party recorded its worst results since the end of apartheid.

The ANC lost its grip on local government seats in Tshwane, the home of South Africa's capital Pretoria.

Results Saturday gave the opposition Democratic Alliance a big win.

Zuma said the results were also a win for South Africa's people.

"We congratulate the people too on the outcome as they are the real victors. Their will must prevail."

The results of the local government elections have reshaped the political landscape in South Africa.

And, the United Nations suspended peace talks Saturday between Yemen's Sunni government and Shiite Houthi rebels.

The U.N. peace envoy, Ismail Ould Cheikh Ahmed, said they could resume within a month.

For more, log on to our website. I'm David Byrd in Washington.

That's the latest world news from VOA.