Swedish police are questioning a man after he was found carrying unauthorised explosives at a nuclear plant.
The man who had entered a nuclear plant at Oskarshamn on Sweden's southeast coast was allegedly carrying highly explosive material.
A spokesman for Kalmar County Police, said police received a call from the Oskarshamn plant at 7:58 a.m. local time.
"They told us a welder who was going to perform a job there had been stopped in a random security check. He had been carrying small amounts of the highly explosive material TATP," Karlsson said.
TATP, or triacetone triperoxide, is an organic peroxide which is more powerful than dynamite but is not on the Swedish Rescue Services Agency's list of banned substances.
"The man has been brought to Kalmar for interrogation," the spokesman said. "The substance has been sealed off at the plant with a 300-metre perimeter."
Oskarshamn is jointly owned by Germany's E.ON and Finland's Fortum. An E.ON spokesman said traces of explosives had been found on the man.
"What has happened is that a guy, a contractor, this morning came to the security check with a bag on which, or in which, there were traces of explosives," E.ON spokesman Johan Aspegren said.
Police spokesman Karlsson said the man has not yet been formally classified as a suspect. He added that bomb technicians had been called in.
State energy firm Vattenfall, which does not run the Oskarshamn nuclear plant but is the main nuclear supplier in Sweden, earlier said it had received word of a bomb threat at the plant.
The police official added he was unaware of any incidents involving other Swedish power plants.
Oskarshamn is one of three nuclear plants in Sweden that meet half the country's power needs. Joint owner Fortum was not immediately available for comment.