North Korean leader Kim Jong-un has ordered the execution of 15 people this year, including several top officials, South Korean intelligence says.

The agency told a parliamentary meeting on Wednesday that they were executed by firing squad on spying charges.
Those killed include two vice ministers who challenged Mr Kim over his policies and members of an orchestra, intelligence officials said.
Mr Kim purged and executed his once-powerful uncle for treachery in 2013.
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South Korean politicians were told that one of the officials killed was a forestry minister who had complained about North Korea's forestation plan, Yonhap news agency reported.
"Excuses or reasoning doesn't work for Kim Jong-un, and his style of rule is to push through everything," said Shin Kyung-min, a member of South Korea's parliamentary intelligence committee, quoting an intelligence official.