Led by Kisan Wing chairman Inderjit Singh Zira and Congress legislature party leader Charanjit Singh Channi the protesters tried to break the barricades, police said.
The cops lathicharged and used water canons to disperse the protesters, police said adding that around 15 members were taken into preventive custody but later released.
The Kisan wing members were protesting against non-payment to farmers for wheat procurement and also raised slogans against the state government.
The Congress claimed that just 40 per cent of farmers have been paid for their procured wheat.
Zira said Congress will soon move the Punjab and Haryana high court against the "losses" being heaped on farmers by the Punjab government.
He claimed farmers had incurred an additional interest burden of Rs 300 crore for delay in payment for their paddy crop last year.
Channi condemned the police lathicharge on peaceful demonstrators.
"Many farmers were injured and few were also taken to government hospital. The protesters were abused by the force and made to run to save their lives also," he claimed.
