Sam Read
BBC Radio Northampton politics reporter

At Northampton railway station buses have arrived to transport commuters to Wellingborough station so they can pick up the Midland Main Line service into London.

It seem to be rather quiet here compared to the scene in Milton Keynes...

Where the queues were much longer...

Image source, South Beds News Agency

And there were more buses...

Image source, South Beds News Agency

Richard Westcott
Transport correspondent

This is going to cause problems on some of Britain's busiest train lines all day and possibly into the weekend.

The fire has damaged a wall right next to the track.

Engineers need to knock the wall down, but to do that they must bring in specialist kit and close the line so they can gain access to the site.

Not a quick job and that's assuming all goes to plan.

If the wall damages a rail as it comes down, for example, it could delay things.

You can catch King's Cross East Coast trains to Scotland/London, but they'll be busier.

Alex Pope
BBC Local Live

If you need to get into London Euston from Northampton or Milton Keynes today, Virgin Trains has just released this map of alternative routes.

Sam Read
BBC Look East

The scene at Northampton railway station is not that chaotic, despite the problems caused by the blaze in Harrow.

There are no queues, which suggests many travellers have decided to stay at home or have found alternative routes by now.

I've spoken to a few frustrated passengers who're not able to get a direct train into London Euston.

Most seem to understand the situation as they realise it can't be helped.

If anyone wants to get into London from Northampton there seem to be a few options.

You either get a train to Milton Keynes and be bused to Luton, or go to Wellingborough station and pick up Midland Main Line services from there.

Kate Bradbrook
BBC Look East

Commuters are now getting on to buses at Milton Keynes railway station to take them to Luton, so they can get into London.

Kate Bradbrook
BBC Look East

The feeling at Milton Keynes station today is one of good humour and resignation.

No trains are running to or from London Euston on the West Coast Main Line, so if anyone wants to travel from Northampton and Milton Keynes to the capital they're having to find alternative routes.

Passengers are being advised to get on buses from MK to Luton.

Several staff from Network Rail, London Midland and Virgin are on hand to advise passengers on the best alternative routes.

Kate Bradbrook
BBC Look East

I've just spoken to Allan Spence at Milton Keynes railway station, who's the head of passenger and public safety at Network Rail.

He told me the company was working "as quick as we can", with an unsafe wall by the line at Harrow needing to be dismantled and rebuilt.

No services will run on the line "until it is safe", he said.

Alternative buses are on offer, saying it was doing its best to get people to their destination.

Travellers are being advised to check the National Rail website before making their journey, external.

Kate Bradbrook
BBC Look East

I'm at Milton Keynes railway station where no trains are going into London Euston today after a fire in Harrow.

It means this rather busy commuter route looks a little different.

Instead travellers are going by bus to Luton to pick up train services there.

Disruption is expected to last for the rest of the day and possibly into tomorrow morning.

Virgin Trains has released a statement after the Harrow fire, which is severely disrupting train services into the capital today from Milton Keynes and Northampton.

As things stand trains can run from Northampton to Milton Keynes, but replacement buses are now operating from MK to nearby train stations.

The company says: "Due to a fire near the railway, which is suspected to have involved gas cylinders, all lines are currently blocked between Euston and Milton Keynes, and there will be significant disruption on other parts of the route.

Image source, @LondonFire

"Other train operators are accepting Virgin Trains tickets so customers can travel on alternative routes, while Virgin Trains has also lifted restrictions so that customers do not have to travel on their booked trains, or can also travel tomorrow instead if they wish.

"We are sorry for the inevitable disruption and delays to journeys."

The retaining wall beside the West Coast Main Line will need to be "dismantled and made safe", says Network Rail.

It explains that the line will be shut all day...

Alex Pope
BBC Local Live

If you need to get into London today from Milton Keynes or Northampton, all the information you need has been released by London Midland trains, which you can see here, external.

East Midlands and Chiltern Railways are accepting London Midland and Virgin Railways tickets.

No services will run between Milton Keynes and Euston at all today, and services from Northampton into London are stopping at Milton Keynes.

Francis Thomas, from London Midland, says only "travel today if you absolutely have to".

Alex Pope
BBC Local Live

The overnight fire at a factory and offices in north-west London will cause train disruption into London from Milton Keynes and Northampton for the rest of the day.

London Euston says the fire has "damaged the trackside retaining wall" and it is a "big job to fix".

The fire-damaged wall is in "danger of collapse and needs making safe before trains can safely run", a spokesman added.

Image source, London Euston

Image source, London Euston

London Midland trains has just confirmed that replacement buses will now run from Milton Keynes to Luton or Bedford so commuters can get into London.

This is because no train services are running from MK into London after a fire overnight in Harrow.

As no trains will be running from Milton Keynes into London today, affecting services from Northampton, Chiltern Railways says it's accepting Virgin Trains and London Midland tickets.

More video footage has been shared online from the Harrow fire, which is affecting train services into London from Northampton and Milton Keynes.

Olivia Weetch filmed the fire last night.

Alex Pope
BBC Local Live

If you are travelling into London from Northampton and Milton Keynes, you are being advised to "put your journey off".

Francis Thomas, from London Midland, says it's "not expecting any services today" along the line, after a fire broke out in a warehouse just before midnight in Harrow.

He says no services are expected to run until the "start of work tomorrow" because of how close the fire is to the railway line and concerns about a retaining wall and gas canisters.

At the moment he says they're "taking it one day at a time".

Image source, @MPSHarrow

Here is the latest from Network Rail...

Below is footage taken of the Harrow fire by Ani Naz.

Nearly 60 firefighters were called to the blaze on Chantry Place, Harrow, close to midnight on Thursday.

As a result, trains through Headstone Lane have been suspended.

London Fire Brigade says a cordon was put in place around the warehouse blaze amid fears propane cylinders might explode.

The blaze is now under control, although 12 residents were told to leave their properties as a precaution.

Alex Pope
BBC Local Live

London Midland trains say that many of their services will be affected by delays today after a fire in Harrow.

The mainline was closed at 00:30 and London Midland services will start from or terminate at Northampton or Milton Keynes.

All services on Virgin Media trains are currently suspended.

Katy Lewis
BBC Local Live

There is major disruption to train services from Milton Keynes into London this morning due to a large trackside fire at a warehouse in Harrow, which broke out at around midnight, and involves gas cylinders.

Image source, Network Rail

The fire closed the mainline about 00:30 and London Midland and Virgin, external services are affected.

Network Rail, external say no trains are able to run between Milton Keynes Central and London Euston.

A spokesman said: "Passengers wanting to travel on the West Coast Main Line are urged to check with their train operator or nationalrail.co.uk, external before travelling as disruption and cancellations are to be expected throughout the day.

"The safety of passengers and staff is our priority.

"We are working with our partners at London Midlands, Southern, Virgin Trains West Coast, Caledonian Sleeper and the emergency services to update passengers as when more information becomes available."

London Midland, external is telling passengers not to travel between Milton Keynes and London Euston.

A spokesman said: "While the emergency services are dealing with the fire it simply isn't possible to run trains through the area."

A further assessment was due to be made at first light, but disruption is expected to last all day.