Sharpening its attack on the government over the new three farm laws, the Congress on Thursday staged a strong protest outside the Congress headquarters here after they were prevented from marching towards Rashtrapati Bhawan. Congress leaders Priyanka Gandhi Vadra and party MPs and leaders staged a sit-in protest outside their office and were detained by the Delhi Police for violating prohibitory orders. The Congress had planned a protest march from the party office at Akbar Road to Rashtrapati Bhawan, where Congress leaders were to meet President Ram Nath Kovind and hand over a memorandum signed by 2 crore farmers. However, the Delhi Police imposed section 144 CrPC around the Rashtrapati Bhawan, including the Congress office, following which the protesting Congress leaders were detained and taken to Mandir Marg police station.