STOCKHOLM, Sweden - A Swedish nuclear reactor was shut down Tuesday for safety checks after an annual review of a similar reactor found cracks in several control rods.
Workers found cracks in at least five of 90 rods of a reactor at the Oskarshamn nuclear plant during annual maintenance work earlier this month. That reactor was closed for maintenance and has yet to reopen.
On Tuesday, officials at the Forsmark plant north of Stockholm said they had shut down one of its three reactors, because it was of the same type as the Oskarshamn reactor with the control rod problem. The Forsmark reactor would be closed for 10 days for inspections, officials said.
Sweden's nuclear watchdog on Tuesday demanded reports on the condition of control rods from all three nuclear plants in the Scandinavian nation.
Swedish Radiation Safety Authority spokesman Anders Bredfell said the problem was serious because the rods regulate the speed with which atoms are split within the reactor.
"We want to know what has caused this," he said. "They are important components in the safety function," Bredfell said, comparing the control rods to the accelerator of a car.
Sweden's three nuclear plants - Oskarshamn, Ringhals and Forsmark - have 10 reactors that provide about half of the country's electricity production.