Story highlights An eyewitness tells local media 20 people were on the bridge when it collapsed

The bridge was privately owned and cost less than $1 for people to cross

(CNN) A wooden foot bridge inside a Colombian nature preserve has collapsed, killing at least seven people and injuring 15 others in Villavicencio, southeast of Bogota, according to the city's mayor.

Colombian risk management authorities said excess weight led to the bridge's collapse Monday.

Continúa la atención tras colapso de un puente colgante zona rural de Villavicencio. https://t.co/KCTepy6eK0 pic.twitter.com/7eH1MUTl3G — UNGRD (@UNGRD) January 10, 2017

An eyewitness told local media that some 20 people were on the bridge when the ropes holding up the left side of it snapped. The bridge stood at a height of 10 to 15 meters (32 to 49 feet).

Two days of mourning have been declared for the city.

Bystanders and rescue workers look for survivors from the collapse.

With Monday a national holiday in Colombia, tourists flocked to the El Carmen preserve. The bridge was privately built and has been privately run since 2004 inside the preserve, according to Villavicencio Mayor Wilmar Barbosa.

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