– Bob Crow, RMT Union
Clearly, there now needs to be a formal and detailed investigation conducted at the highest level as this is not the first time our members have reported door malfunctions on the ageing Piccadilly line fleet.
– Nigel Holness, London Underground
Safety systems immediately alerted our train operator after a Piccadilly line train travelling to Heathrow on Sunday was found to have two doors slightly open.
The operator brought the train to a halt, checked the doors and ensured they could be fully closed before the train was taken to the next station where it was taken out of service.
The safety of our customers and staff is our highest priority and the train remains out of service while we carry out an investigation.
The doors of a packed London Underground train have opened between stations in West London.
The Rail Maritime and Transport union claims a baby in a buggy was close to the door that partially opened on the Piccadilly line train on Sunday.
The union says the incident raises questions about the reliability of the trains, which it says are 40 years old but were not due to be replaced for another decade.
Service is suspended on the Piccadilly Line westbound between Cockfosters and Acton Town due to a signal failure at Arnos Grove.
There is also no service between Acton Town and Rayners Lane due to planned engineering work.
A good service s in operation on the rest of the line.
Severe delays on the Piccadilly Line are set to continue as emergency work is being carried out 'for at least another half an hour'.
The signal failure occurred early this morning leading to the line being closed between Kings Cross and Hyde Park.
Follow Transport for London on Twitter for updates.
No service between Hyde Park Corner and Kings Cross due to emergency engineering work at Green Park. Severe delays on the rest of the line while we fix a signal failure at Green Park.
Tickets will be accepted on London Buses, Heathrow Connect and First Capital connect (GN) via any reasonable route. Greater Anglia are accepting tickets between Liverpool Street and Enfield Town
Minor delays on Piccadilly Line Eastbound due to signal failure at Turnham Green.
Service suspended on Piccadilly Line between Hammersmith and Hyde Park Corner and minor delays on the rest of the line due to person under a train at Earls Court. Tickets being accepted on local buses, and First Capital Connect services.
Underground station closed on Piccadilly Line at Earls Court due to person under train.