Seoul, Mar 18 (IANS): The investigation into an influence-peddling scandal involving former South Korean President Park Geun-hye will likely take a new turn as prosecutors plan to question her next week, top officials announced on Saturday.

Prosecutors sent a summons to Park earlier this week to appear for an interrogation on Tuesday, after the Constitutional Court removed her from office on March 10, Yonhap News Agency reported.

"We are creating a questionnaire," a senior prosecutor said on Friday, adding it is yet unclear how long it will take to complete the inquiry.

Ahead of the rare interrogation, prosecutors intensified their probe, summoning a number of company executives and government officials embroiled in the scandal.

Three former and incumbent executives of SK Group were questioned on Thursday over bribery allegations in connection with Park's close friend Choi Soon-sil.

The nation's third-largest conglomerate is suspected of donating 11.1 billion won ($9 million) to two dubious foundations, allegedly controlled by Choi, in return for business favours.

Choi, at the centre of the scandal, is standing trial over multiple corruption charges, including extorting money from local conglomerates in collaboration with the former President.

On Monday, prosecutors questioned two employees in charge of duty-free shops at the Korea Customs Service (KCS) over suspicions that local conglomerates, such as SK and Lotte, made huge contributions to the foundations in return for favours in winning licenses to run the lucrative shops here.

Lotte was selected by the KCS to operate the shop, along with five other conglomerates, in December. SK was not included in the list.