Chinese prosecutors are planning an eight-month crackdown on environmental and food safety crimes after detaining 13,495 suspects for such offenses last year.

This is a year-on-year rise of 12 percent, figures from a Thursday press conference showed.

Senior Supreme People's Procuratorate (SPP) official Wan Chun said a nine-month campaign against lax investigation and prosecution was launched in April 2013. It led to thousands of criminal cases related to people's livelihoods being transferred from police and other law enforcers to prosecutors.

More than half of these cases involved food safety and environmental issues, while others concerned agriculture, health and education, labor insurance and other fields, Wan said.

In one case revealed earlier by the SPP, suspect Liu Liguo sold "gutter oil" made from kitchen waste worth 100 million yuan ($16.31 million) between December 2007 and July 2011. Some 9 million yuan's worth of the unsafe oil entered the market.

Liu was given a life sentence in 2013.