An explosion and fire at a Gibraltar power station which blacked out much of the British outpost also caused major worldwide disruption to the online betting industry, with gambling giants William Hill and Ladbrokes among the operators taken offline.
A power station generator exploded on Sunday because of mechanical problems, said police and government officials on the tiny British-held peninsula on the southern tip of Spain.
As thick smoke billowed over the territory, police told nearby residents to keep their windows closed to avoid breathing problems.
No one was harmed, police and a spokesman for the Gibraltar government said.
But the blaze interrupted Gibtelecom services, bringing down worldwide betting services such as Ladbrokes, William Hill and Betfred. Some were still battling to resume their operations yesterday.
Gibraltar's low taxes have lured 26 major online casinos and gaming operators. Authorities in Gibraltar claim that 60 per cent of all online gambling transactions flow through its territory.
William Hill said the blaze forced its services offline for about two-and-a-half hours.
Some 50 employees at the William Hill offices adjacent to the fire were evacuated by police and firefighters, said spokesman Graham Sharpe.
"It is just one of those freak events nobody could have predicted," Sharpe said, offering apologies to customers.
"There will be those who will claim they would have backed a winner but there will be others who have been saved from backing a loser," the spokesman said.
William Hill operations had returned to full strength, he said.
Ladbrokes said it, too, was hit as the fire interrupted Gibtelecom's communications network linking the territory with the rest of the world.
"We apologise to the customers who were affected by the loss of some of those services on Sunday afternoon and have been working hard and successfully to restore these," Ladbrokes said in a statement.
"None of our staff were affected by the incident, and no customer data was compromised during that period," the betting company said.
Betfred's internet site was still down yesterday.
"Please be aware that all services are currently down, we're working hard to resolve this issue & will update all customers once resolved," said the latest tweet update by Betfred.
A number of online poker operators were also taken offline as a result of the blaze and blackout.
Gibraltar police said investigators had ruled out foul play in the power plant fire.
Late in the evening, the head of Gibraltar's government, Chief Minister Fabian Picardo, said power had been restored to the whole territory.
"At last. Power outage too long. New plans must reflect lessons of such incidents so we never repeat," Picardo added in a message on Twitter.
Spain ceded Gibraltar to Britain in perpetuity in 1713 but has long argued that it should be returned to Spanish sovereignty, and the territory remains a source of diplomatic tensions.
Spain's tax office has reportedly set up a working group to analyse tax payments made in Gibraltar, suspecting that Spanish company earnings escape its clutches.
Gibraltar denies such claims.