BEIJING - Prosecutors investigated more than 8,000 people on suspicion of breach of duty in the first half of 2014, according to statistics released by the Supreme People's Procuratorate (SPP) on Friday.

They include 303 officials at or above the county level, which represents a year-on-year increase of 21.2 percent, said Li Wensheng, chief of the SPP's anti-duty dereliction bureau.

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Those investigated include 33 officials at the bureau level, up 266.7 percent from the same period a year earlier, he said.

Prosecutors also investigated 503 suspects for possible criminal actions behind major accidents, including a tanker explosion in north China's Shanxi Province that killed 40 people. Eight officials were accused of dereliction of duty and abuse of power after the explosion.

Prosecutors in the second half of 2014 will tighten the crackdown on official misconduct in food and drug safety, environmental protection and land acquisition, Li said.