(LEAD) N. Korea's earthquake may not be due to H-bomb test: spy agency
(ATTN: ADDS more details from lawmaker in last 3 paras)
SEOUL, Jan. 6 (Yohap) -- An artificial earthquake detected in North Korea may not have been caused by a hydrogen bomb, a ruling party lawmaker said Wednesday, citing South Korea's spy agency.
North Korea announced earlier that it has successfully carried out a hydrogen bomb test, hours after a 4.8-magnitude earthquake was detected in an area 49 kilometers north of Kilju, home to the Punggye-ri nuclear test site.
"North Korea claims it was a hydrogen bomb, but there is a possibility that it may not be the case," Lee Cheol-woo of the ruling Saenuri Party said, citing the magnitude of the quake.
Lee made the comments to reporters after attending a closed-door parliamentary session of the National Intelligence Service (NIS) in southern Seoul.
The NIS said its assessment is based on the yield of the nuclear device. It said the yield of a hydrogen bomb should be more than 100 kilotons, but the yield of Wednesday's test is 6 kilotons and a 4.8-magnitude temblor was detected, Lee said.
In comparison, the yield of the nuclear device North Korea tested in 2013 was 7.9 kilotons and it caused a 4.9-magnitude earthquake.
The spy agency also assumed that North Korea carried out the test as part of its efforts to show some kind of accomplishment to its people ahead of the 7th Workers' Party Congress set for May.
"(North Korea) previously informed of its nuclear tests to China and the United States a day before," Lee said, noting that Pyongyang did not provide any prior notification this time.
North Korea previously carried out tests of nuclear devices in 2006, 2009, and 2013.