An armed tribesman loyal to Houthis steps on a US flag during an anti-USA and anti-Israel rally, in Sana'a, Yemen, 29 January 2024. (Photo by Yahya Arhab/EPA/EFE)

A protester aims a sling shot at police in Santiago, Chile, September 1989. (Photo by Marco Ugarte/AP Photo)

Carnival revellers take the metro in Rio de Janeiro, Brazil on February 19, 2023. Shaking the ground to the beat of their drums, Rio de Janeiro's famed carnival parades returned Sunday in a swirl of glitter, sequins and samba, the festival's first full-on edition since Covid-19 and Brazil's bitterly divisive elections. (Photo by Carl de Souza/AFP Photo)

Tourists watch roaring torrent carrying a large amount of yellow sediment at the Hukou Waterfall on the Yellow River on August 15, 2024 in Yan'an, Shaanxi Province of China. (Photo by VCG/VCG via Getty Images)

More than 6 billion people live in countries where serious levels of public sector corruption are fueling inequality and exploitation, according to Transparency International's 2015 index of perceived public sector corruption. The group's annual report measures perceptions of corruption due to the secrecy surrounding most corrupt dealings. Two thirds of the 168 countries assessed were identified as having a serious corruption problem. Somalia, which has been mired in conflict since civil war broke out in 1991, ranks bottom of the list. (Photo by Feisal Omar/Reuters)

The first seal pup to be born this season at a major colony of grey seals on the Farne Islands sits beside its mother on Brownsman Island, England on September 30, 2015. (Photo by Owen Humphreys/PA Images)

The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

Police fire rubber bullets as they help an Atletico Paranaense fan during clashes between Vasco da Gama soccer fans and Atletico Paranaense fans at their Brazilian championship match in Joinville in Santa Catarina, on December 8, 2013. Dozens of fans fought a savage battle on the terraces at the match on Sunday, interrupting play for more than one hour and leaving at least three people reportedly in serious condition. (Photo by Carlos Moraes/Agência O DIA)