The ropes holding a wooden bridge together snapped Monday at Colombia's El Carmen nature preserve.

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.

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.

In an interview with local radio Blu Blu, Barbosa said the owner of the bridge would charge less than $1 for people to cross it.

Authorities are investigating the accident and said they will hold the responsible parties accountable.

Barbosa added that health personnel is working with the families of the victims and those injured.