LANZHOU, Jan. 31 (Xinhua) -- Procuratorate in northwest China's Gansu Province confirmed Sunday they have launched an investigation into the arrests of three journalists.

The provincial procuratorate told Xinhua they had sent an investigation team to Wuwei City, where the reporters were arrested, and would make the results known to the public.

The reporters from three local newspapers were reported missing in Wuwei on Jan. 7. Local police on Jun. 9 said one reporter was detained for involvement in a prostitution case, but changed the wording days later, saying the three were detained on racketeering charges.