Forty people elected in the April 13 parliamentary elections are being investigated for election-related offenses, police said Thursday.

Of the 40 lawmaker-elects under the probe for allegedly violating the Public Official Election Act, 10 people are allegedly involved in illegal donation, the National Police Agency said.

Twelve people are investigated over suspicion of spreading lies about rivals, followed by seven who may have conducted illegal pre-campaigning, according to the NPA.

The NPA said it has investigated a total of 2,036 people in connection with election offenses in the lead up to the polls that picked the 300-member National Assembly.

Officials said the method of election violations have been clearly shifting from bribery to spreading false information. 

In the latest elections, the main opposition Minjoo Party and the People's Party won 123 and 38 seats, respectively. The ruling Saenuri Party secured just 122 seats. (Yonhap)