The youngest son of South Korean President Kim Dae-jung has returned to Seoul from the United States to face questioning from prosecutors about an influence-peddling scandal. The alleged bribery affair has gripped South Korea, and has led a decline in President Kim's popularity.

Witnesses said Kim Hong-gul, one of President Kim's three sons who has been living in the United States, arrived home Tuesday from California to meet the prosecutors' Wednesday afternoon deadline to answer a summons for questioning.

The allegations of influence peddling swirling around the president's youngest son have sent shockwaves through the ruling Millennium Democratic Party, ahead of local elections next month and a presidential election in December, and forced President Kim to apologize to the nation and resign from the party.

The prosecution, some observers say, comes at an awkward time for the government, as it tries to showcase South Korea ahead of the World Cup soccer championship starting later this month.

"This whole story is very demoralizing for the South Korean public and of course it is very disappointing for Kim Dae-jung and his supporters," observed Scott Snyder of the Asia Foundation.

"It does detract from legacy that he had hoped to leave. At this point they are conflicting desires. The one important thing is that prosecution is proceeding according to rule of law. I think that is the positive thing but at the same time, the public and the government also would prefer to be focusing on preparation of world cup and people are focusing on who will be Kim Dae-jung's successor," said Mr. Snyder.

The president himself has not been implicated in any scandal, though his administration has been accused of swapping favors for money. His single five-year term ends in February, and by law he cannot seek re-election.

Kim Hong-up has denied wrongdoing. His younger brother has not made any public comment about his case, which reports say involves accepting $219 million in bribes from high-profile lobbyists seeking government contracts.