Community health workers have been shocked by the theft of a potentially life-saving defibrillator machine from its Ipswich Waterfront site.
The kit, which is used in resuscitating victims of heart attacks, was housed in a former red telephone box on Stoke Bridge - and the thieves even took the door.
Joe Joskow of the Community Heartbeat Trust (CHT), a charity which helps communities install the kits, said the details would now have to be reported to the ambulance and other emergency services so it could be taken off line.
He said: "We had been told the door of the cabinet had been taken off, and thrown in the river, and the defibrillator was missing.
"Sadly it proved to be true. If the door had still been in place I could have put in a temporary unit.
"It is very disappointing but fortunately it is quite a rare occurrence. The number stolen is probably below 50."
Mr Joskow said the CHT monitored 5,000 defibrillators within the community across England, Scotland and Wales.
The machines are added to a national database available through the ambulance and other emergency services.
Mr Joskow said: "These are important pieces of equipment and the trust looks after them across the country."
Mr Joskow said the incident was now being investigated by the police and he urged people to contact officers of they had any information.
Defibrillators are becoming an increasingly common sight in the high street as businesses and charities raise money to have them installed in easily accessible public places.
The defibrillator is charged and when switched on gives a range of recorded instructions to the operator on how to use it in an emergency.
Twin paddles are applied to a patient's chest to deliver an electrical charge across the heart to stop it, allowing it to reconfigure automatically.
Mr Joskow said: "There are a growing number of de-fibs in place across Ipswich, though they are not all on the database."
The incident has angered local business people.
Cafe owner Kie Humphreys hit out at the thieves, saying: "This is just mindless vandalism. No-one is going to buy it anyway so it is pointless.
"Potentially this could save someone's life."
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