A power cut in central London this morning left two Tube stations and guests at a hotel in a blackout.
Euston and Russell Square stations were temporarily shut as the electricity went off, while guests at the nearby Hilton were left without heating, hot water, lifts, hot food or telephones.
More than 800 households and businesses lost power, some for more than four hours, the supplier confirmed.
Even after power was restored to the Tube stations, many still appeared to be in the dark about when the lights would be back on.
Tracy Fletcher tweeted at the hotel chain: "Any news on power cut at Euston? Currently laid in bed fully clothed. Power been off 2.5 hours."
And Carol Frend wrote: "Same here - getting cold [and] need to get to work. No power #poweroff #nowater #nolift #nobreakfast #help."
<blockquote class="twitter-tweet" lang="en"><a rel="nofollow" target="_blank" href="https://twitter.com/HiltonHelp" class="body-link" data-vars-item-name="BL-76901-https://twitter.com/HiltonHelp" data-vars-event-id="c23">@HiltonHelp</a> any news on power cut at Euston currently laid in bed fully clothed. Power been off 2.5 hours <a rel="nofollow" target="_blank" href="https://twitter.com/hashtag/nohotwater?src=hash" class="body-link" data-vars-item-name="BL-76901-https://twitter.com/hashtag/nohotwater?src=hash" data-vars-event-id="c23">#nohotwater</a>— Tracy Fletcher (@tracy_fletcher) <a rel="nofollow" target="_blank" href="https://twitter.com/tracy_fletcher/status/580979248581607424" class="body-link" data-vars-item-name="BL-76901-https://twitter.com/tracy_fletcher/status/580979248581607424" data-vars-event-id="c23">March 26, 2015</a>
UK Power Networks confirmed supplies were fully restored at about 7.40am.
"At 3.24am today 854 customers experienced a power interruption," a spokeswoman said. "The majority of supplies were returned to normal by 5.53am, with the final reconnection by 7.38am.
"We apologise to customers for any inconvenience caused and our engineers restored power as quickly as possible."
