Police in Camden will carry Tasers from this month as part of a controversial programme to arm thousands of officers in the capital with the stun-guns.

On Friday the first Camden officers hit the streets armed with the stun-guns, which deliver electric shocks of up to 50,000 volts to the body. At any given time there will be four police officers armed with Tasers patrolling the borough.

The roll-out is part of an £800,000 programme, announced by the Metropolitan Police at the start of last year, to arm 40 officers in every London borough with Tasers.

When the programme was rolled out in Haringey in March this year, borough commander, Chief Superintendent Victor Olisa, said that Tasers were a “fantastic option” to deal with violent situations.

He said: “It is probably the best equipment we could have to deal with violent situations. With tear gas, the wind has to be going in the right direction otherwise everybody surrounding it is crying, while the person you are trying to subdue, it does not even get anywhere near them.

“Then we have the baton – a piece of metal which is a weapon in anyone else’s hands. It can cause some damage. So the Taser is a fantastic option.”

The Met says that in 85 per cent of cases involving Tasers, the mere presence of a stun-gun has been enough to bring a potentially violent situation to an end without any physical contact.

The force says Tasers also serve to protect police officers and are only used in situations involving violence or potential violence where there is a need to protect the public or police.

But civil liberties groups have pointed to accidental deaths and the use of Tasers on the mentally ill as causes for concern.

Mind In Camden, which works in the area of mental health, has also raised specific concerns.

A spokesperson said: “Tasers are extreme and controversial weapons that we believe should only be used as a last resort. Tasers can cause extreme distress, so to use them on people who are experiencing a mental health crisis, and already displaying signs of distress, can make things even more traumatic.’’

Cllr Abdul Hai, Camden Council cabinet member for community safety, said he is concerned that Taser training is not good enough. He is “firmly opposed” to the plans and will be making his views known to Camden’s borough commander.

“I’m concerned that this is putting weapons classified as firearms into the hands of officers who have not been provided with the level of training the public expects,” he said.

But the Met says the three-day training course is rigorous and the use of Tasers by officers will be strictly monitored.

Simon Marcus, a Conservative councillor for Hampstead, who worked with gang members through a boxing club he established in Tottenham, applauded the opportunity for Tasers to be used as a deterrent.

He said: “Having worked with gang members in high crime areas and as a member of the Government Riots Panel I believe the Taser, when used carefully, has the potential to save many lives.

“Tasers are a good way of having police do their job safely, of acting as a deterrent, and avoiding injuries and fatalities among the police.”

He added: “If police had been able to use Tasers during the riots – and don’t forget, people died – lives could have been saved and communities could have been saved, because the situation would not have escalated.”

Critics also say that electric shocks can lead to heart attacks and this risk is heightened if the person has been using drugs.

Police currently use Tasers in 20 London boroughs and by time the programme is rolled out across the capital, the Metropolitan Police will have a stock of 1,590 Taser guns.