China have protested on the streets and surrounded government offices demanding help recovering money from a get-rich-quick scheme to raise ants to make an aphrodisiac tonic.

Hundreds of anti-riot troops and police in Shenyang,capital of Liaoning province, were deployed to stop protesters reaching the provincial government and Communist Party headquarters, residents said on Wednesday.

The irate investors from across Liaoning, a rustbelt province striving to attract investment, have demonstrated in Shenyang since Monday and sporadic clashes with police have broken out, they said.

Several thousand protesters gathered near the provincial government offices on Wednesday, a resident told Reuters by telephone.

The investors - many of them laid-off workers or farmers - put their savings into Shenyang's Yilishen Group for a scheme in which they raised ants to provide ingredients for a health tonic promising an aphrodisiac boost.