While the VHP observed the day as 'Shourya Diwas (valour day)', Samajwadi Party marked it as 'Kala Diwas (black day)'.
All India Babri Masjid Action Committee has decided to organise special prayers for peace and harmony.
Officials said, "In Ayodhya, besides central forces, 500 personnel of PAC, 200 jawans of Rapid Action Force, three bomb detecting squads and anti-sabotage teams have been deployed."
CCTV cameras were in operation at the disputed site with the authorities banning public gatherings and security forces keeping a close vigil on the Saryu river here.
Additional Director General (Law and Order) Brijlal said, "District police chiefs have been asked to ensure that the programmes held by different organisations to mark the occasion did not vitiate communal harmony."
He also said RAF teams have been deployed in Faizabad, Gorakhpur, Lucknow, Moradabad, Aligarh, Varanasi, Mau, Kanpur and other districts.
According to sources, public places including railway stations, bus stands and markets were kept under surveillance to avert any attempt to disturb law and order.