The main accused was taken into custody yesterday itself, but today police arrested him and three others.
Accused Vikram Kumar, a convener of the Aam Aadmi Party's (AAP) Dhanaula Committee, was held at the spot, but his accomplices who, police said, had "updated" a senior AAP leader about the incident, were arrested later.
Ludhiana Range DIG G S Dhillon, in a release here, said the four arrested were Vikram Kumar of Dhanaula, Mahinderpal Singh of Dangarh, Harvinder Singh of Barnala and Hardeep Singh.
Questioning of the arrested persons has revealed that they had conspired that Vikram Kumar would hurl the shoe and a video of the incident would be made by Mahinderpal Singh by using his mobile phone. This video was to be uploaded over YouTube, Whatsapp, Facebook and other social networking sites for maximum publicity.
He revealed that on pursuance of the conspiracy, Vikram, Mahinderpal, Harvinder and Hardeep came to the venue of the function in a car and parked the vehicle in the general parking area.