Abellio Greater Anglia says following a fault with the signalling system at Norwich station all lines have now re-opened.
Four train services between Norwich and Cambridge and Norwich and London remain cancelled on Tuesday evening.
The rail company apologised to passengers and said trains were now able to run normally after Network Rail engineers made the necessary repairs.
Trains in and out of Norwich station are being delayed or cancelled because of a signalling fault. It's affecting all routes from Norwich.
Engineers are on the way to the scene but as yet Greater Anglia say they don't know how long the disruption will last.
Due to a fault with the signalling system at Norwich some lines are blocked. Train services to and from this station may be subject to disruption on all routes. An estimate for the resumption of normal services will be provided as soon as the problem has been fully assessed.
- 1735 Norwich to Cambridge which was due in at 1859
- 1800 Norwich to Liverpool St which was due in at 1955
- 1925 Cambridge to Norwich which was due in at 2041
- 2030 Liverpool St to Norwich which was due in at 2229
Travellers using Abellio Greater Anglia trains from Norwich into London know only too well it's been a frustrating year thanks mainly to overrunning engineering work and other related issues.
Whether it's any consolation, from the New Year they'll be travelling in more comfort and style than they've been used to.
The rail operator is spending £10million on refurbishing the mainline fleet - a task that'll take nearly two years.
Click below to watch a report from ITV News Anglia's Kate Prout
A signalling fault near Stowmarket that has disrupted rush hour trains between Suffolk, Norfolk and Cambridgeshire has been fixed although delays are expected well into the afternoon.
"Train services between Norwich and Liverpool Street, Ipswich and Cambridge, and Ipswich and Peterborough will be disrupted until further notice, whilst the train service is restored. This involves getting the booked traincrew and trains back into the correct places. Some train services may still be cancelled, have their stopping patterns changed, or started at another station or terminated short of their destination."
Abellio Greater Anglia says ticket restrictions have been lifted for the remainder of Thursday 18 December so passengers travel on other trains than specified on their advance purchase tickets.
There's major disruption on trains between Ipswich and Norwich because a signalling fault near Stowmarket.Read the full story ›
Service suspended on Abellio Greater Anglia between Stowmarket and Ipswich due to signalling problem at Stowmarket.
Delays of up to 30 minutes on Abellio Greater Anglia between Ipswich and Cambridge, and between Ipswich and Bury St Edmunds due to signalling problem at Stowmarket.
There are Monday morning problems for train commuters into London.
There are delays and cancellations on the Abellio Greater Anglia rail line between Norwich and the capital through Essex, Suffolk and Norfolk.
Over-running engineering work at Seven Kings in London has blocked two of the four metro lines and they will be closed until at least 8am.
#SevenKings - Due to over-running engineering works, Mainline trains may be cancelled or delayed up to 20 minutes via Stratford. JA
The 0622 train from Norwich to Liverpool St was cancelled because of a person being hit by a train between Ingatestone and Chelmsford on Sunday night.
Train tickets are being accepted on London Underground and some Transport for London bus services.
The rail line between Norwich and London has been plagued with problems in recent months after weekend engineering work was not cleared in time for the Monday morning rush hour.
It looks like being another frustrating morning for Greater Anglia passengers.
There's disruption on trains between Colchester and London Liverpool Street due to a broken down freight train at Kelvedon.
The train is now on the move again, but Greater Anglia say that the problems could continue until at least 10am.
#Chelmsford - Due to a broken down freight train, all services via Chelmsford are using platform 2 with delays up to 30mins possible. JA
#Chelmsford - This problem is affecting trains in both directions between Norwich, Ipswich, Colchester, Clacton, Braintree & London. JA
There is currently major disruption on Abellio Greater Anglia trains between London Liverpool Street and Norwich due to overhead line problems between Marks Tey and Witham in Essex.
Tickets being accepted on London Underground, Cross Country, East Midland and Great Northern train services.
Train services may be cancelled or delayed by up to 60 minutes and disruption is expected until 3pm this afternoon.
Liverpool Street – Norwich services are running between Norwich & Colchester only. Customers are advised to travel via Cambridge and Ely for connections to London & Norwich.
Liverpool Street – Clacton-on-Sea services are running between Clacton & Colchester only. Rail replacement buses are running between Colchester & Witham, with a train service forward to London.
Liverpool Street – Braintree services are running between Witham and Braintree only.
Abellio Greater Anglia tickets are being accepted on London Underground services between Liverpool Street and King's Cross, Great Northern train services between London King's Cross and Ely, and on East Midlands Trains services between Ely and Norwich, in both directions until further notice.
CrossCountry trains are accepting Abellio Greater Anglia ticket holders between Ely and Stansted Airport via Cambridge for passengers travelling via West Anglia services.
Replacement buses are operating between Witham & Colchester, with some buses serving Kelvedon & Marks Tey.
Customers with advance purchase tickets are advised that restrictions have been lifted, and they may travel earlier or later today than the time specified on their ticket.
We thank you for your patience, and apologise for the delay and disruption to your journey today. Network Rail Engineers are on site and are working as quickly as possible to make repairs to the damage.
We would like to make you aware of our delay repay policy which can be found on the Abellio Greater Anglia website.
Click here to be directed to the Abellio Greater Anglia website.