The three-hour nationwide "chakka jam" blockade of national and state highways -- by farmers protesting against the Centre's farm laws was held amid a high alert in Delhi today. Highways across north India, including the Eastern Peripheral Expressway around Delhi were blocked by farmers protesting against the centre's three farm laws passed in September. In Bengaluru, 30 people were taken into preventive custody. "We won't return home unless our demands are met", said farmer leader Rakesh Tikait, whose emotional outburst after the violence during Republic Day's tractor rally gave a second wind to the protest being held by lakhs of farmers at the borders of Delhi for more than two months.