Modi arrived at the fast venue at the State Reserve Police ground in Godhra at 11 am where he was greeted by his cabinet colleagues and local MPs and MLAs, besides BJP leaders and priests from various religions.
A huge crowd had gathered at the venue from all sections the society from across Panchmahal district to witness Modi's day-long fast, as part of his Sadbhavana Mission.
Godhra, the epicenter of communal turbulence in 2002, has transformed virtually into a police base camp ahead of the day long fast.
Over 1,600 policemen have been deployed along with 50 specially trained Chetak commandos and other unarmed jawans across the town.
The fast is being held nearly a month before the tenth anniversary of Godhra carnage where 59 persons, mostly karsevaks were killed when the S-6 coach of the Sabarmati Express train was burnt near Godhra Railway station on February 27, 2002 trigerring worst ever riots in the state.
Earlier, even before the fast meant to promote peace, harmony and brotherhood could begin, social activist Shabnam Hashmi and five others of NGO Anhad were detained for organising convention 'In search of Justice'.
Police said they were detained as they wanted to hold a public function despite their request for permission was rejected.