Croydon commuters into central London are squeezing onto one of the most packed train services in the country, data reveals.

The 6.32 Southern service from Caterham to Victoria - leaving at 6.35 until a March 2015 timetable change - is the sixth most overcrowded service in England and Wales, according to a list released today by the Department for Transport (DfT).

A count carried out last autumn at Clapham Junction found a crushing 704 commuters using the service, squeezed into space designed for just 430 passengers - a 164 per cent increase on standard capacity.

The only London train services more choked both terminate at Paddington: the 7.57 Heathrow Connect service and the 6.31 First Great Western service from Reading.

At the same time in 2013, the Caterham train was running at 149 per cent capacity.

Network Rail estimates overall passenger numbers will increase by 40 per cent in the next three decades.

The DfT said: "Currently there are no more carriages available to lengthen this train or to run any additional trains between East Croydon and London Victoria unless they were taken from other trains, but that would cause crowding elsewhere."

A Southern spokesman said: "The 06.35 (now 06.32) Caterham to London Victoria service was introduced in 2011 to plug a half-hour fast gap that existed between East Croydon and London Victoria.

"The service is formed of four carriages – the maximum number available. Since its introduction, the service has proved so popular that it has now become heavily crowded.

"To mitigate against this, in December, the 06.09 Southern service from Horsham to London Victoria will be lengthened from eight to 12 coaches when the timetable changes.

"The Horsham service shares stops with the Caterham train (Purley, East Croydon and Clapham Junction) and we envisage that passengers will migrate from the Caterham train to the Horsham train at these stations, helping to reduce crowding on the Caterham service."