North Korea's top official in charge of relations with South Korea has died in a traffic accident, the country's state media announced Wednesday, dimming the prospect for ties between the rival countries. He was 73.

Kim Yang Gon, head of the United Front Department at the ruling Workers' Party, died Tuesday morning, the Korean Central News Agency reported. It said a state funeral will be held Thursday for him but gave no further details about his death.

He was the first senior North Korean official who state media said died in a car accident since young leader Kim Jong Un took power upon the death of his dictator father Kim Jong Il in late 2011. State media have occasionally reported about deadly traffic accidents involving other top officials without elaborating.

North Korea has poor road conditions. However, many previous announcements about traffic deaths involving officials have spawned rampant outside media speculations of possible state assassinations linked to fierce power struggles, and that Pyongyang had fabricated the cause of their deaths.

None of those speculations has been independently confirmed as it's almost impossible to verify what is exactly happening among the ruling elite in the secretive, authoritarian North. But similar speculations again appeared in the South Korean media following Kim Yang Gon's death, though without any substantial evidences. South Korean officials refused to comment.

Before his death, there had been no signs that Kim Yang Gon was engaged in any major factional feuding with other officials. He was among officials who most frequently accompanied Kim Jong Un during his inspection visits to army units and factories, a strong indication that he was one of the leader's trusted aides.

Wednesday's KCNA dispatch described him as the leader's "closest comrade-in-arms and steadfast revolutionary comrade" who had made "dedicated" efforts to push for unification with South Korea.

Analysts in Seoul say strained ties between the rival Koreas could continue following the unexpected death of Kim, who had long handled relations with South Korea. The KCNA did not say who would replace him. Earlier this month, the rival Koreas ended rare high-level talks without any agreement.

"I worry that we cannot avoid long suspension of a dialogue between South and North Korea" following Kim's death, said Cheong Seong-chang, at the private Sejong Institute in South Korea.

In August, Kim Yang Gon attended marathon talks at the Korean border that defused a military standoff trigged by land mine explosions blamed on Pyongyang that maimed two South Korean soldiers. The two Koreas subsequently resumed their first reunions of families separated by war since early 2014, but hopes of improved ties subsided after this month's inter-Korean talks failed to reach any breakthrough.

South Korea's Unification Minister Hong Yong-pyo sent a message of condolence Wednesday, according to Hong's ministry. South Korea has previously offered similar condolences when senior North Korean officials died.

Kim Yang Gon visited South Korea in 2009 to pay his respects to late President Kim Dae-jung, who held the first inter-Korean summit with Kim Jong Il in 2000. He was believed to have played a key role in arranging a second summit in 2007. Most rapprochement agreements signed after the two summit talks remain stalled or have never been implemented after animosities flared again between the rivals.

The Korean Peninsula remains in a technical state of war since the 1950-53 Korean War ended with an armistice, not a peace treaty.

A list of people forming Kim Yang Gon's funeral committee includes Choe Ryong Hae, another close associate of Kim Jong Un who South Korea's spy agency said last month was banished to a rural collective farm for re-education. South Korean media reported Choe's involvement in the funeral as a sign that he might have restored his power.

The report by Seoul's National Intelligence Service might also have been wrong given it has a mixed record of tracking developments in North Korea. The spy service said Wednesday it was trying to check details about developments about Choe.

Choe's reported banishment had been seen as the latest in a series of executions, purges and dismissals that Kim Jong Un has orchestrated in what outside analysts say was a further strengthening of his grip on power.