The tailbacks caused by a fatal crash on the A12 were the worst recorded in the UK last month.

Commuters were caught in 12.5-mile queues following the tragic accident on the A12 at Marks Tey on February 18.

A car carrying four generations of a family overturned on the northbound carriageway at 3.25pm and all five occupants were injured.

Great-grandmother Iris Hadden, 78, of Colchester, was taken to Addenbrooke’s Hospital, Cambridge, where she later died.

The road was closed off until 9.30pm that evening to allow traffic officers to conduct inquiries.

Now figures released by TomTom’s HD Traffic Centre show the ensuing tailbacks were the worst in the UK during February.

A spokesman for the SatNav company said: “In the evening rush hour, there was a 12.5-mile tailback at 7.06pm between Chelmsford North and Colchester North.

“The worst point of the evening was at 7.46pm, when there was a 104-minute hold-up between Chelmsford and Marks Tey.”

Inspector Steve Brewer, of Standway Road Policing Unit, explained that the crash scene spanned three lanes, making it impossible for emergency crews and investigators to work without closing the road.

He added: “Being a Friday and the start of the school half term there was a heavy volume of traffic and because the crash happened on the Ipswich-bound side of the Marks Tey on-slip, traffic had to be diverted off the A12 and then allowed to rejoin further up.

“It is not possible to get three lanes of A12 traffic through Copford and Stanway without severe congestion.”