Power supplies to most parts of southern Sweden and eastern Denmark resumed this afternoon after a two-hour power cut, Swedish national grid operator Svenska Kraftnat said.
"Most of the power supply to southern Sweden and [the Danishisland of] Zealand are back in operation after restoration,"Svenaka Kraftnat said in a statement to Nordic power exchange Nord Pool.The outage had cut power to millions of consumers.
Power went out in the early afternoon, apparently after a storm hit transmission lines in Sweden.
At least three nuclear power stations with combined capacity of about 3,000 megawatts in Sweden went off stream, and power was cut throughout the Zealand island where the Danish capital Copenhagen is located.
Copenhagen airport was closed for all landings and takeoffs, incoming flights were redirected or returned, an airport spokeswoman said. The Copenhagen Metro said two trains were caught underground but both were emptied of passengers without problems.
State railways said trains all over Zealand were stopped and passengers were asked to remain inside.
Public radio news said hospitals were running on emergency power, and the Oeresund Bridge linking Denmark to Sweden was closed.
The blackout, highly unusual in Scandinavia, follows the huge power cut that left 50 million North Americans without power for up to two days in August.