SEOUL (REUTERS) - South Korean investigators on Thursday (Nov 24) raided the offices of Lotte Group, SK Group and government agencies as part of a widening probe into alleged influence-peddling that has engulfed President Park Geun Hye, Yonhap news agency reported.

The raids came a day after prosecution investigators carried out related searches at offices of Samsung Group, South Korea's largest family-run conglomerate and the parent of global smartphone leader Samsung Electronics Co Ltd.

The businesses are suspected of providing money to organisations controlled or owned by Choi Soon Sil, a close friend of Ms Park, to win government favours in relation to duty free licences, Yonhap reported.

A Lotte Group spokesman confirmed the company's offices had been raided but gave no further detail. An SK Group spokesman had no information on the matter and a prosecution spokesman was not available for comment.

The finance ministry and customs service, which oversee duty free licences, were also raided, Yonhap reported. A finance ministry official confirmed the raid but a customs official had no information.

Ms Park and Choi are under investigation for allegedly improperly pressuring major conglomerates including the Samsung Group, South Korea's largest family-run conglomerate, to raise funds for foundations that backed Ms Park's policy of promoting the cultural and sports communities.

Choi and and former presidential aide An Chong Bum were indicted on Sunday and charged with abuse of power, in a major blow to the president's fight for political survival.