The three-hour nationwide "chakka jam" blockade of national and state highways -- by farmers protesting against the Centre's farm laws is being held amid a high alert in Delhi today. A group of farmers have blocked the Eastern Peripheral Expressway around Delhi and the highway at Haryana's Palwal along with several others. The farmers have said there will be no blockade in Uttar Pradesh and Uttarakhand in case they are "called to Delhi". In Bengaluru, 30 people have been taken into preventive custody.