Within minutes, technicians had set up an emergency telecommunications centre with satellite phone lines and high-speed internet connections. Relief organisations were quick to avail themselves of the service. Satellite lines were made available to hospitals and to link survivors with the outside world.

The initiative was the work of Télécoms sans Frontières (TSF), a new charity backed by companies including Vodafone, Cable & Wireless and Inmarsat.With fixed-line and mobile networks down, the victims in many of the tsunami-struck regions — as in other disaster zones — had no way of finding out whether relatives were alive, nor of contacting friends and family in other countries to provide help.

Speaking from a refugee camp in the Hambontota district, in southeast Sri Lanka, Oisin Walton, 25, a full-time member of TSF, explained that the use of a satellite phone had provided not only a physical help but a huge psychological uplift to the tsunami survivors. “It is just amazing the difference a simple call can make,” he said. “You can see it in the faces of these men and women who have literally lost everything.”

That morning the group had helped one woman to track down her son, who was based in a navy ship near to the coast where the tsunami hit. “When she heard his voice the tears were streaming down her face,” Mr Walton said.

Over the next ten days Mr Walton and his team will roam between refugee camps in the area, providing this new-style help. A second TSF crew, from the group’s Asian base in Bangkok, is gearing up to join them.

Once the normal phone networks are up and running, their job will be done and they can return home.

The man behind TSF is Jean-François Cazenove, a former worker with France Télécom, the French telecoms group, who now works full-time out on the ground with the charity.

M Cazenove launched TSF in 1998 after realising that, along with medicine and food, there was a real need for telecommunications in disaster zones. On assignment in Kosovo, he realised how desperate people were to communicate with others. Mr Walton said: “People kept presenting him with pieces of paper with their relatives’ numbers on, asking if he would call them. The next time he went out he took one satellite phone and literally several hundreds of people were queuing to use it.”

With communication networks destroyed or jammed, it can be hugely difficult for rescue teams to co-ordinate their actions and for families to communicate.

However, the advance of technology and the shrinking size of electronic equipment has made it increasingly easy for mobile teams to respond in all kinds of terrain and in all kinds of situations.

TSF, which is based in Pau, France, has played a major role in relief efforts in crisis areas such as Baghdad, the Philippines and Grenada.

The organisation has only six full-time paid members. The rest of the 20-strong crew is made up of volunteers from every sector of industry. When disaster strikes, they aim to be in the affected regions within 24 to 48 hours.

Vodafone, which has just donated £100,000 to TSF to help its work in the tsunami- affected regions, says: “Emergency telecommunications are a critical aspect of any humanitarian rescue operation.

“TSF’s ability to contribute satellite phones and high-speed internet connections in affected areas is a great benefit to aid organisations in their decision-making.”

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