Mexico earthquake: Who are the hero 'moles' of Mexico City?

Hit by two powerful quakes in less than two weeks, Mexico City is reeling from the disasters that have claimed hundreds of lives, demolished buildings and left thousands homeless.

And as emergency services battle to locate and free survivors, they are being helped by a group of volunteer rescue workers known as the 'moles' - but who are they?

Topos de Tlatelolco

The volunteer search and rescue group formed more than 30 years ago, when a group of youths - all from the working class neighbourhood of Tlatelolco - pulled victims from the rubble of Mexico's 1985 quake which killed over 5,000 people.

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Calling themselves Topos de Tlatelolco (Tlatelolco Moles), the volunteers spontaneously organised days-long rescue operations after the devastating quake, filling in the gaps for overwhelmed and underprepared government.

Formally founded five months later in February 1986, one of the group's original founders - Hector 'El Chino' Mende - defined the group by saying they had the "balls to go in where no one else will".

Why do they do it?

As volunteers, they are not paid for their work.

Oscar Guevara, a doctor from the central Mexican state of Queretero who joined in 2010 and is now helping in Mexico's search efforts, says the "intense emotion" of finding someone alive is all the motivation he needs.

Mr Guevara said: "Obviously it is a point of pride to be helping here. But we are trained to give the same reply in Mexico or overseas".

Do they only work in Mexico?

No, the team have worked at disaster sites across the world including the 2001 attacks on the World Trade Center in New York where they helped look for bodies at Ground Zero and the 2004 tsunami in Indonesia.

Assisting in at least 22 countries so far, they have travelled to disasters in Haiti, Nepal and the Philippines.

Some of the team have only just returned from assisting in relief efforts in the US after Hurricane Irma.

Each volunteer lists the countries in which they have served on their typical uniform of a red T-shirt, worn along with a yellow hard hat.

What are their skills?

Initially the group had no formal search and rescue qualifications, but now on enrolling they are trained in areas such as rescue strategies, managing collapsed structures and risk management.

With the help of the Civil Protection Agency of Mexico the moles also sponsor technical degrees in areas related to the field, and issue certificates.

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What do they do?

The team specialise in earthquakes and landslides but also have experience in vertical rescue, water rescue, landslides, medical emergencies, fires and floods.

They locate and triage victims; clear rubble and and bodies and help develop long-term recovery plans.

They also participate in international disaster training programs.

What equipment do they have?

As they travel on commercial airlines, they travel light to adhere to baggage restrictions.

Simple tools such as ropes, spikes, shovels, hammers, axes and electric saws form the majority of their equipment.

They also carry stretchers and medical equipment.

The team are also assisted by search and rescue dogs who are trained with the help of Mexico City's ambulance corps and the Mexican Red Cross.

Where does the money come from?

As a non-profit civil association, the team receive little government support, and raise most of their money through fundraising .

They have also developed a survival device able to send out the geocoordinates of victims buried under rubble, with sales helping fund training and future rescue trips abroad for volunteers.

Saving lives

So far the team have pulled three people alive from ruins in Mexico City following the latest quake.

Although regularly risking their lives to save others, no team member to date has been killed while on duty.