From Washington, this is VOA news. I'm Steve Karesh reporting.

If the deteriorating cease-fire in Syria is to be salvaged, U.S. Secretary of State John Kerry said Wednesday that warplanes must stop flying over "key areas" of the country, including places where humanitarian agencies are trying to deliver food and medicine.

"So I believe that to restore credibility to the process, we must move forward to try to immediately ground all aircraft flying in those key areas in order to de-escalate the situation and give a chance for humanitarian assistance to flow unimpeded."

After flagrant violations of the Syrian cease-fire agreement forged earlier this month by the U.S. and Russia, including a deadly airstrike that destroyed an aid convoy on Monday, John Kerry said all sides in the conflict are at "a moment of truth."

He made his appeal to a high-level meeting of the U.N. Security Council, saying that a limit to overflights is crucial to limiting the bloodshed.

U.S. President Barack Obama addressed the second U.S. Africa Business Forum on the sidelines of the U.N. General Assembly on Wednesday to promote trade and investment in Africa.

The forum began two years ago and the president said "you can see the results today."

"American investment in Africa is up 70 percent. U.S. exports to Africa have surged. Iconic companies -- FedEx, Kellogg's, Google -- are growing their presence on the continent. You can hail an Uber in Lagos or Kampala."

Obama said that all growth is "scratching the surface" of Africa's economic potential, but it's important for African nations to promote "good governance that allows for good business."

He added that "graft and cronyism scares off investment."

This is VOA.

Police in Charlotte, North Carolina, are bracing for more violent street protests after [an American] an African-American officer shot and killed a black man Tuesday night.

The violence injured about 24 people, including 16 officers, when protesters threw rocks at police and reporters and set a truck on fire. Part of a busy inner state highway were shut down and police used tear gas to break up the crowd.

Charlotte Mayor Jennifer Roberts pledged a "thorough and transparent" investigation into the shooting, calling for peace, calm and dialogue.

The legal crackdown in Turkey continues on followers of Islamic cleric Fethullah Gulen, who is being blamed for a failed coup. With tens of thousands arrested, opposition parties are starting to voice concern that the crackdown is turning into a witch hunt. Dorian Jones reports.

The latest official figures indicate more than 100,000 people have been removed from their state jobs and 60,000 detained or arrested. The firings and arrests are primarily aimed at followers of Gulen blamed for the failed military takeover attempt in July.

Turkish President Recep Tayyip Erdoğan has promised no let up on the crackdown, warning it will be expanded overseas.

He says, "No country or region will be safe for members of the Gulen movement, we will hunt them all down."

Experts claim Gulen followers number in the hundreds of thousands in Turkey and have built a wide network of businesses, private schools and supporters across the Turkish state.

Dorian Jones, of VOA news, Istanbul.

Pakistan's Prime Minister Nawaz Sharif reiterated on Wednesday that only a dialogue between the Afghan government and the Taliban can end decades of conflict and suffering in neighboring Afghanistan.

Speaking to the annual U.N. General Assembly, Sharif said his country has been helping with the Afghan reconciliation in response to requests from Afghan President Ashraf Ghani.

Sharif spoke just hours after Afghan Vice President Sarwar Danesh, in his speech to the U.N., alleged that terrorist attacks against Afghan civilians are originating in Pakistan.

Despite numerous calls on Pakistan to destroy terrorist havens, Danesh said authorities there have not acted.

U.S. economic officials held the key interest rate steady at a near-record low level on Wednesday, but said the case for raising rates "has strengthened."

Many experts interpret that as a signal that the U.S. Federal Reserve may boost interest rates in December. The Fed repeated a pledge that whenever it does begin to increase borrowing costs, it will do so gradually.

Reporting from Washington, I'm Steve Karesh. This is VOA.

That's the latest world news from VOA.