Most of the strikes are taking place at peak times for motorists, between 6am-8am and 5pm-7pm.

Road accidents now make up the majority of the fire service’s call-outs because firefighters are often required to help remove injured people from wreckages.

The Fire Brigades Union have launched the eight-day strike over what it calls a “vicious” attack on pensions that are “unacceptable”, “unworkable”, and “unrealistic”.

As well as proposing to extend firefighters’ retirement age from 55 to 60, the government has imposed a third annual increase in how much firefighters pay in to their pensions, taking it to 14.2 per cent for most of them.

The FBU say this means that a firefighter with a salary of less than £29,000 now pays around £4,000 a year for a pension that is being devalued and attacked.

Matt Wrack, FBU general secretary, said: “The government must realise that firefighters cannot accept proposals that would have such devastating consequences for their futures, their families’ futures, and the future of the fire and rescue service itself.

“We have tried every route available to us to make the government see sense over their attacks.

“Three years of negotiations have come to nothing because the government is simply unwilling to compromise or even listen to reason despite a huge amount of evidence showing their planned scheme is unworkable.

“Shorter strike periods have illustrated the strength of feeling amongst firefighters whilst limiting disruption to the fire service, the public and our members’ working lives. But the government is merely ploughing ahead, forcing firefighters to react.”

The strikes are taking place between 6am-8am and 5pm-7pm from Monday 14th July to Thursday 17th July, and on Monday 21st July.

On Friday, the strikes are between 6am-8m and 11pm-1am, and on Saturday between 11am-1pm and 11pm-1am. Sunday’s strikes take place between 5pm-7pm.

Thirty-three firefighters also took part in the public sector strikes on Thursday 10th July.