Another day of rail chaos on the main line to London has prompted further calls for major new investment on the route that carries tens of thousands of commuters to the capital.

The line was closed for hours during the morning rush yesterday after a major signal failure at Chelmsford.

No trains were able to get through the station after the fault was detected at 5.45am until 9.30am when a temporary manual system was set up. That only allowed a restricted low-speed service through that section.

It was caused by a technical fault in cabling near Chelmsford station.

The fault was repaired by 11am but it took several more hours for services to return to normal because many trains were in the wrong place.

Train operator Greater Anglia urged anyone who did not have to travel to London yesterday to delay their journey or find an alternative route.

The problems on the railway came after two major road incidents affected travellers in east Suffolk and north Essex over the last few days.

On Friday The A14 at Nacton was partially closed after a lorry crash – causing major problems for traffic in and around Ipswich.

And on Monday the northbound A12 near Marks Tey in Essex was closed for 13 hours after a fruit lorry overturned.

Suffolk’s cabinet member for transport said the problems faced by travellers over the last few days showed up the desperate need for investment in the region’s road and rail network.

Graham Newman said the region had been ignored by central government for much too long – and even now planned improvements were not keeping pace with the growth in demand.

He said: “When you look at what Network Rail is proposing to invest in the Great Eastern main line it is looking at the situation we have now – but demand is increasing all the time and it is not going to keep up with that demand.”

Mr Newman felt that in his discussions with Network Rail about investment, everything seemed to be concentrated on boosting freight services – but passenger growth was at least as important for the industry.

Since privatisation in 1996 the number of passengers travelling from Suffolk to London every year has doubled.

And projections show that the number of passengers in the region are expected to rise by at least 75% over the next 30 years – and many experts feel that is a serious under-estimate.

Mr Newman also feels that investment on the region’s major roads has been inadequate.

“That is why we are very keen to get an upgrade to the A14 in Cambridgeshire – even though we are very concerned about the toll proposal. We desperately need to improve our links with the rest of the country.”

Ipswich MP Ben Gummer avoided yesterday’s rail chaos but had been caught in Monday’s problems on the A12.

He said: “It is interesting that this problem happened on the most congested section of double track in the country, precisely where we are urging Network Rail to put in an extra track.”

Mr Gummer pressed the case for investment in the region’s rail network when Transport Secretary Patrick McLaughlin visited the region in August.