From Washington, this is VOA news. I'm Jonathan Jones reporting.

Iranian President Hassan Rouhani says his people have the right to protest and criticize the government. It's his first public response to the nationwide anti-establishment protest that have stretched throughout Iran into a fourth day.

Iranian state media said Rouhani made the conciliatory comments about the protests in remarks to his cabinet on Sunday. But they also quoted Rouhani as saying the protesters should focus on solving the country's problems and improving people's lives.

Iran's biggest and most sustained anti-government protests since 2009 continued Sunday, with hundreds of people joining street rallies in several parts of the country.

The Iranian government on Sunday blocked people from using social media, the platform Instagram and the messaging app Telegram.

Iranian state television said authorities were temporarily blocking both applications to "maintain peace."

Many protesters had been using the apps to upload or share photos and videos from the demonstrations.

South Korea announced Sunday it had seized another ship it suspects transferred petroleum products to North Korea in violation of international sanctions. The announcement said the Panama-flagged ship was detained two weeks ago at a port.

It's the second ship the South Korean government has acknowledged investigating in the past three days. On Friday, it announced that it had seized and inspected a Hong Kong-flagged ship in November because it believed the tanker transferred oil to a North Korean vessel mid-ocean.

This is VOA news.

U.N. Secretary-General António Guterres warns that the world is likely to face many complex and new dangers in 2018. In a year-end message, Guterres appealed for greater unity to overcome these threats and create a more peaceful world.

Correspondent Lisa Schlein reports for VOA from the U.N.'s European headquarters in Geneva.

Guterres says he is issuing what he calls a red alert for our world.

"Conflicts have deepened and new dangers have emerged. Global anxieties about nuclear weapons are the highest since the Cold War and climate change is moving faster than we are. Inequalities are growing and we see horrific violations of human rights. Nationalism and xenophobia are on the rise and as we begin 2018, I call for unity."

During this past year, Guterres has had many catastrophic events landing on his desk begging for resolution.

As the world's leading diplomat, Guterres must retain his sense of optimism that things can get better. He says the world can be made safer and more secure; conflicts and hatred can be overcome. But, only, he adds if world leaders unite to bridge divides and bring people together around common goals.

Lisa Schlein, for VOA news, Geneva.

At least 30 people died Sunday when a bus and a truck collided in central Kenya. Eighteen people were injured in the wreck.

The Star newspaper reports the bus was traveling in the wrong lane at the time of the accident.

A suicide bomber killed at least 18 people in an attack targeting the funeral of former district chief in eastern Afghanistan's Nangarhar province.

There was no immediate claim of responsibility. But shortly after the attack on Sunday, the Taliban denied any involvement.

Five sheriff's deputies and two civilians were shot as police responded to a domestic disturbance call Sunday in the Midwestern U.S. state of Colorado.

The Douglas County sheriff's office said one of the five deputies had been killed and the suspect was shot and believed to be dead and no longer a threat.

More than two decades after the U.S. state of California became the first to legalize medical marijuana use, on January 1, it becomes the final West Coast state to legalize marijuana for recreational use.

There is more on these and other late breaking and developing stories, from around the world, around the clock, at voanews.com and on the VOA news mobile app. I'm Jonathan Jones reporting from the world headquarters of the Voice of America in Washington.

That's the latest world news from VOA.