The team said in a press release that Park was an accomplice of her friend Choi Soon-sil, who took bribes from the Samsung company in exchange for business favors.
The investigators believe Park and Choi used phones registered under names of other people to communicate 573 times between April and October 2016.
The suspended president is also said to have been involved in blacklisting 9,473 liberal-leaning cultural figures, who were critical of her policy, Sputnik reported.
Political scandal around the South Korean president broke out in late October 2016, when media reported that Park had allowed Choi influencing the country's policy. The scandal resulted in Park's impeachment in December 2016.
Last week, the Constitutional Court had its final hearing and is expected to produce a final verdict upon the validity of the parliament's impeachment of Park before March 13. If the court approves the impeachment, the presidential election is to be held within 60 days after the ruling.