A total of 129 officials at prefectural level or above have been investigated for suspected corruption and bribery in the first eight months of this year, the Supreme People's Procuratorate said on Thursday.

Prosecutors nationwide investigated 22,617 cases involving 30,938 people on suspicion of corruption between January and August, the top procuratorate said in a statement.

The number of cases was 3.6 percent higher than the same period last year, while the number of people investigated increased by 3.8 percent, and 7,080 of the cases came via tips from the public, the statement said.