Chandigarh, June 8 : Protesting farmers in Haryana have warned authorities to immediately release their nine leaders, including Bharatiya Kisan Union (BKU) state president Gurnam Singh Charuni, who were sent to custody for 14 days for blocking the National Highway-44 earlier this week, otherwise a massive rally would be held on June 12. On Thursday, farmers continued with their solidarity protests at various places in Punjab and Haryana demanding their release. A day earlier, the arrested farm leaders were produced before a court that remanded them to a 14-day judicial custody. Besides charges pertaining to rioting, they are facing cases for unlawful assembly, use of criminal force to deter public servants from discharging duty and attempt to murder. BKU leader Rakesh Tikait on Wednesday threatened a larger agitation than the year-long protest against the now repealed farm laws if the government did not announce a legal guarantee of the minimum support price (MSP) for procurement of crops. Tikait, who reached Shahabad in Kurukshetra district, to extend support to the agitating farmers and those who were arrested, condemned the police lathicharge on protesting farmers who had blocked a national highway on Tuesday demanding that the state government should procure sunflower seeds at the MSP. Claiming that the MSP for crops is a pan-India issue, he said: "This is the first lathicharge in the country on those demanding MSP. The struggle that began in Shahabad would reach the national level as every farmer is concerned about the MSP for different crops. An agitation bigger than the one in Delhi will have to be undertaken for the MSP." Charuni's son Arshpal Singh told the media that the government should release the leaders and start procurement at the MSP by June 12, or they will intensify the protest. "Farmer unions from Haryana, Punjab and Uttar Pradesh will gather at the Pipli grain market for 'MSP dilao, kisan bachao' rally on June 12 to chalk out a strategy and take some big decisions. All small sit-in protests being held at various locations will be lifted and only one will continue at Shahabad." The farmers have been demanding procurement of sunflower seed at the fixed MSP of Rs 6,400 per quintal. On May 30, the BJP-led government included sunflower seeds in the list of crops covered under the Bhavantar Bharpai Yojana (BBY), under which Rs 1,000 per quintal is provided to farmers for selling their produce to private buyers. Shahabad legislator Ram Karan Kala, who is a leader of the Jannayak Janta Party (JJP), a BJP ally, said he would resign from his post as the chairman of the Haryana Sugar Federation if the state government failed to accept farmers' demand to procure sunflower seeds at the MSP within 24 hours. /IANS