Colombia’s second city has been forced to take drastic measures to combat the dizzying levels of pollution that the city is experiencing.

Medellín (the name is pronounced “Me-de-jeen”, by the way) was once famed for being the world’s former murder capital. Today, it’s seen as an innovation and tourist hub, too.

But, according to pollution watch-dog AQICN.org, the city currently has worse pollution than Mexico City (another Latin American city famed for its poor air quality). At the time of writing, the north of Medellín is experiencing pm2.5 levels – the number of micrograms of particles smaller than 2.5 thousandths of a millimetre across in an average cubic metre of air – of 154 µg/m3. That’s two points higher than the most polluted area of Mexico City, and 15 times higher than recommended safe levels.

In response to the crisis, over the weekend, the city’s mayor, Federico Gutiérrezn, issued orders banning cars and motorcycles from the road for 27 hours, and restricted the when and where dumpster trucks can operate in the coming days. He even announced the suspension of outdoor activities – including sports events and cycle paths – to protect citizens’ health.

The move followed a brief spell the previous week that saw Medellín Olaya Herrera – the city’s smaller, domestic airport – close. Although now re-opened, local sources are unsure as to how long the airport will continue to operate while pollution levels continue to increase.

In a press statement, Gutierrez explained that Medellín’s bowl-like geography – the city lies in the middle of the Andean Aburrá Valley – has played a significant role in the city’s pollution crisis. “The landscape helps accumulate the pollutants emitted in the valley,” he said. But he added that everyone who pollutes had, in some way, contributed to the current problems.

Medellín’s government first declared an emergency over the city’s air quality in the middle of March, citing a lack of rain, and the effects of weather phenomenon El Niño for the problem. Causing extreme heat and a lack of rain, the effects of El Niño have been further exacerbated by forest fires and dust particles from the Sahara Desert. The result of all this is that pollution has collected in the Aburrá Valley instead of dispersing.

That said, of course, the largest contribution to the dangerous pollution levels comes from the human population. In recent years the proportion of Medellín’s 3m inhabitants that own a car or a motorbike has increased. And while the government has introduced contamination limits for vehicles in Medellín – including for trucks and buses – these often go ignored.

Medellín is not the only city in Latin America to ban cars from the roads this week, either. Authorities in Mexico City have also ordered that all vehicles must remain off the roads for one day a week, in a bid to quickly lower the proportion of pm2.5 particles in the air. The Mexican capital has often struggled with pollution levels: like its Colombian counterpart it sits in a bowl from which it is difficult for pollutants to escape.

Medellín now awaits the arrival of rains in April that will help wash the pollution away. Hopefully.