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More than 100 people are estimated to have died in a huge landslide that struck the remote village of Kaokalam in Papua New Guinea's Enga province on Friday.
It's the latest in a series of deadly landslides to have occurred in the country in recent months, after 14 people were buried alive in Simbu province in April, and at least 21 people died in three separate landslides across the country in mid-March.
Sadly, the fatalities are not a new development for Papua New Guinea, which regularly experiences fatal landslides that don't make headlines beyond its borders.
Let's take a look at why PNG is so prone to this type of natural disaster, why it costs so many lives, and what the rest of the world can do to help.
Why does PNG see so many landslides?
Dave Petley, vice-chancellor of the University of Hull in the United Kingdom, is a globally recognised expert on landslides who runs The Landslide Blog for science magazine Eos.
He attributes PNG's regular landslides to a number of specific factors, chief amongst them being the country's deeply weathered, mountainous terrain and tropical climate.
Heavy rain and storms lead to increased erosion, flooding and higher tides, all of which raise the chance of dangerous rockfalls, he says.
Add to that the fact that the country sits on the Ring of Fire — a string of active volcanoes and high seismic activity that runs along the border of two tectonic plates in the Pacific — and you have perfect landslide conditions.
"You have regular significant earthquakes, which of course trigger landslides in their own right, but also weaken the rock slope," Professor Petley says.
"The whole area is very tectonically active."
Why have so many people lost their lives?
The factors that make landslides so common in Papua New Guinea are certainly problematic, but they are by no means unique to the country.
The reality is landslides occur fairly regularly in certain regions of the world.
Countries where they are common include the United States, Japan, Italy, Austria and Switzerland — hilly or mountainous countries with inclement weather.
So why does PNG in particular seem to experience deadly incidents so regularly?
People who study the issue have long been able to draw a connection between landslide fatalities and economic development — as is the case with earthquakes, and most natural disasters in general.
All things being equal, the poorer a country, the more fatalities they will likely experience.
There are a number of reasons for this — poorly built infrastructure, less effective emergency responses, low availability of healthcare and a lack of early warning systems among them.
A fifth factor, as outlined by earth sciences professor A Joshua West for The Conversation, is development patterns that determine where people live.
Papua New Guinea is one of the world's most rural societies.
Its population is officially 10.5 million, but there are indications the true figure could be much larger — as high as 17 million, according to a UN study — due to a lack of proper record-keeping.
Either way, less than one-fifth of PNG's known population lives in urban centres, and the majority of those that live elsewhere depend on subsistence farming, which needs a certain amount of land.
Given the country's growing population and hilly landscape, this means people are more likely to live in areas at risk of landslides — areas which are also harder for emergency services to reach.
Does human activity play a part?
In addition to the geological and weather conditions outlined above, Professor Petley attributes Papua New Guinea's regular landslides to another major factor — human disturbance.
Alongside small villages and farms, PNG's forests play host to a number of large industries that create conditions where landslides can become more likely.
Gold, silver, nickel, copper and cobalt are all mined in the country, and LNG operations have been taking place in areas where deadly landslides occurred in the past.
PNG also has a large illegal logging industry, as well as being the world's fifth-largest exporter of palm oil, which requires extensive deforestation.
"Put simply, this is a landscape which should be forested, and the forest has been removed," Professor Petley says.
Are things getting worse?
PNG's deforestation problem shows no sign of improving, with satellite imagery showing logging activity continuing to rise.
The country is also struggling to roll out key infrastructure, let alone undertake the sort of large-scale engineering projects that would be needed to make landslides less dangerous (or improve the emergency response).
Loading...In the meantime, climate change — itself exacerbated by deforestation — is making extreme weather events more likely, as well as contributing to higher king tides as global sea levels rise.
Residents of Lese Kavora, a coastal village, in March began discussing potential options for relocating the entire village, after king tides damaged food gardens and contaminated their drinking water.
Professor Petley says climate change has a particularly pronounced effect on landslide activity because it results in more eclectic weather systems, with sudden changes in conditions overwhelming the landscape's ability to cope.
"Slopes are particularly sensitive to short-duration, high-intensity rainfall events," he says.
"You can go back to first principles — imagine a landscape evolves to deal with the most intense rainfall it experiences.
"If you increase that intensity, you're taking the landscape into an environment it's never experienced, and it will respond. And a landslide is the inevitable response.
How can the rest of the world help?
To a certain extent, landslides in mountainous environments are inevitable — and to the extent that climate change continues to worsen, extreme weather events that trigger them are now baked into the system.
But the effect of those landslides, both in the number of fatalities and the nature of the response, can be mitigated, most experts say.
Growing Papua New Guinea's local economy, rather than undertaking large-scale engineering projects, would be a major step in the right direction.
Professor Petley also points to Nepal — where massive Himalayan landslides have previously claimed hundreds of lives — as a success case for reforestation.
"In areas where there have been proactive attempts to reforest [in areas where people are vulnerable], we do see a significant drop in landslides," he says.
He agrees consumers in other countries can help slow deforestation in PNG by reducing demand for palm oil products and illegally sourced timber.
"We also need, globally, to tighten up the way we're managing mining, both in the way we treat the land and also dispose of the waste," he says.