内容摘要：Within moments, a 13-year-old boy has been arrested and we're back outside in the morning light. The family screams on the front lawn as the camera returns to the boy, now a detainee in the dark interior of a police van.

Within moments, a 13-year-old boy has been arrested and we're back outside in the morning light. The family screams on the front lawn as the camera returns to the boy, now a detainee in the dark interior of a police van.

Sebastião Salgado, regarded as one of the world's greatest documentary photographers, has died at the age of 81.The Brazil-born photographer was known for his dramatic and unflinching black-and-white images of hardship, conflict and natural beauty, captured in 130 countries over 55 years.

His hard-hitting photos chronicled major global events such as the Rwanda genocide in 1994, burning oilfields at the end of the Gulf War in 1991, and the famine in the Sahel region of Africa in 1984."His lens revealed the world and its contradictions; his life, the power of transformative action," said a statement from Instituto Terra, the environmental organisation he founded with his wife, Lélia Wanick Salgado.Some of his most striking pictures were taken in his home country, including epic photos of thousands of desperate figures working in open-cast gold mines and striking images of the indigenous people of the Amazon.

Brazilian President Luiz Inácio Lula da Silva paid tribute, describing Salgado as "one of the best... photographers the world has given us".Salgado's final major project, Amazônia, spotlighted the rainforest's beauty and fragility.

A lifelong advocate for the Amazon's indigenous people, Salgado documented the daily lives of a dozen of the tribes scattered throughout the rainforest - from hunting and fishing expeditions, to dances and rituals.

He spent seven years on an ambitious photographic journey, exploring the remote reaches of the Amazon rainforest and documenting its inhabitants.Its policy adviser, Bushra Khalidi, also questioned how vulnerable people, such as the elderly, would be able to reach these sites, which are located some distance away from some population centres.

When the UN had been delivering aid before Israel's humanitarian blockade, there were 400 distribution points spread across Gaza. Under the present GHF distribution system there currently are four known sites."By and large, it's designed to dramatically increase the concentration of the population by having the only sources of food remaining in a very small number of places," said Chris Newton, a senior analyst at the Brussels-based think tank Crisis Group.

"You either follow all their rules and probably survive in a small radius around these sites or you are very unlikely to survive."The presence of armed security and Israeli soldiers at or near the distribution sites has also alarmed experts, who said it undermined faith in aid operations.