LONDON — A number of workplaces, museums and other buildings were still closed Thursday a day after a cable fire in central London, which resulted in a mass evacuation and widespread power outages.

See also: Mass evacuation and power cuts after fire in central London

London Fire Brigade said it still had firefighters and officers at the scene in Kingsway where it said a cable tunnel fire was under control but not fully extinguished.

“This has been a technically difficult incident to tackle. The reason that the fire is still burning is because the service tunnel is hard to reach and although firefighters have been applying water through access points throughout the night, the complexity of the tunnel layout means that it will be some time until the fire is fully extinguished," London Fire Brigade Assistant Commissioner Peter Cowup said in a statement Thursday morning.

“However, the fire is contained and we are making steady progress and working with the utility companies and the police to bring this incident to a close.”

@blathnaidhealy Holborn is still smoking away this morning. pic.twitter.com/9kTBcqEooT — Ben Maher (@Maherster) April 2, 2015

Parts of Kingsway, a major road in Holborn, and surrounding streets were cordoned off by the Fire Brigade.

UK Power Network, which supplies electricity to the area, said in a statement Thursday that it couldn't yet access its equipment as the fire was still not extinguished.

@johnny_alucard Hi Johnny. We are currently hoping that our engineers will have the power back on at some point today, However due to the // — UK Power Networks (@UKPowerNetworks) April 2, 2015

"Our engineers have restored power to 2,000 customers and the remaining 1,100 will regain power through generators and cable works as soon as possible," it said.

There have been no injuries and the cause of the fire is not yet known.

Some businesses in the area were tweeting customers Thursday, warning of closures.

Morning everyone. Due to the #HolbornFire our office is still shut and our server is down - sorry if you're trying to reach us. — ITB Agency (@itbagency) April 2, 2015

The #HolbornFire has had a big effect on the West End. This is a sign at @ShakeShackUK in Covent Garden currently. pic.twitter.com/nUq0Ogcanz — Andrew Havis (@AndrewHavis) April 2, 2015

Institutions like the London Transport Museum are still closed.

NOTIFICATION: The Museum remains closed due to #holbornfire. We aim to reopen as soon as possible. Apologies for any inconvenience caused RT — LTMuseum (@ltmuseum) April 2, 2015

The building is still without power & will remain closed to public & tenants until power is restored, we will update when we have more news — Somerset House (@SomersetHouse) April 2, 2015

Due to a power outage in the area the Hunterian museum is now closed until Tuesday. We wish you all a happy Easter and long weekend. — Hunterian Museum LDN (@HunterianLondon) April 2, 2015

As darkness fell over the are Wednesday night, it was possible to see the extent of the power outage.