Updated

A special investigation team is wrapping up its probe into a huge scandal involving impeached President Park Geun-hye after the country's acting leader refused to extend its investigation past a Tuesday deadline.

Faced with massive street protests, Park was forced to approve the launch of the investigation team led by independent counsel Park Young-soo before she was impeached by parliament in December over allegations she let her longtime confidante meddle in state affairs and extorted money from companies.

The team has since arrested a slew of high-profile figures, including former Park administration officials and Samsung heir Lee Jae-yong, in connection with the scandal. The team, whose investigation is to end Tuesday, had asked acting leader and Prime Minister Hwang Kyo-ahn to allow 30 more days of investigations. Under the law they can seek such an extension.

But Hwang's office said Monday it had rejected the request because the investigation team has already indicted key figures implicated in the scandal and that state prosecutors can look into any possible remaining areas of the scandal.

Hong Kwon Heui, a spokesman for Hwang, told a televised news conference that a longer investigation could sway a possible presidential election that would happen if the Constitutional Court approves President Park Geun-hye's impeachment. The court is expected to rule in March on whether to formally end Park's rule or restore her presidential powers.

Lee Kyu-chul, a spokesman for the investigation team, described Hwang's decision as "very regrettable."