The accident took place at around 19:34 on 30 January 1958 and was a rear-end collision of two late-running trains. Conditions at Dagenham East station were foggy at the time. The accident occurred after one train had passed a signal indicating danger due to a driver error. Ten passengers were killed in the accident and 89 injured. Four members of railway staff were also injured.
The trains involved were the LMS 2-6-4 tank engine hauled 18:20 Fenchurch Street to Shoeburyness and the BR standard 2-6-4 tank hauled 18:35 Fenchurch Street to Thorpe Bay. Both trains consisted of 11 coaches, carrying approximately 500 passengers each. The 18:35 train ploughed into the back of the 18:20 departure which demolished three carriages and derailed several others. The locomotive of the 18:35 train and leading carriage were derailed. Some wreckage blocked the adjacent London Underground line but did not cause any further accidents.