Hello and welcome to NewsHour from the BBC World Service.

I'm Celia Hatton, and I'm coming to you live from our studio in London.

Coming up on the program today, Thailand and Cambodia have been arguing over their border for years.

We'll explore why fresh fighting has broken out now.

And how many steps do you really need to walk every day to stay healthy?

You might be surprised by the answer.

But first, we'll start this edition of NewsHour in Haiti.

We've gained rare access to the Haitian capital, Porto-Prince,

where gangs now control 90% of the city.

The police there are outnumbered and outgunned.

Government authority has all but collapsed,

and ordinary Haitians are trapped in a daily struggle for survival.

In the last six months, more than 4,000 people have been killed.

Cuts to US aid are compounding the crisis, leaving already vulnerable communities without food, health care or protection.

Over a million people have been forced to abandon their homes, and it's women and children who are suffering the most.

And here, I want to warn you.

The report we're going to bring you now

contains upsetting content relating to sexual violence.

The names of the people we've interviewed here

have been changed to protect their identities.

In Haiti, one in five victims of sexual violence is a child,

and some victims of rape are as young as six.

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