As Bachchan was busy shooting for Shoojit Sircar's "Piku" in north Kolkata during the day, hundreds of fans gathered there, prompting the actor to praise the city as the "most dedicated unit of humans that have unique abilities within, to cheer and win the hearts of us all".
"Each day from the hours in the morning to the hours late at night they stand there in discipline and wait for the celebrities to emerge, to express their love, to express their affection their dedication, their appreciation of the work donea this lot this happy lot, this merry lot of wishers.
"They are not subjected to any kind of compulsion, nor are they compelled... they are just what Kolkata is, was and shall remain ever - a passionate, loving, most dedicated unit of humans that have unique abilities within, to cheer and win the hearts of us all," Big B wrote in his official blog Saturday night.
In the crowd was a scrawny youth clad only in white running shorts, goggles and sports shoes.
Holding a bunch of documents, he sportingly faced the photographers with 'Amitabh' written on his bare torso and arms.
Failing to meet the star, he handed over the documents to Bachchan's security detail.
"I think the person with 'Amitabh' scripted all over him has a problem. I think he has an ailment and he needs help. I saw him in the crowd trying to attract my attention, but security was too tight...
"I shall investigate and see if I can be of some assistance... he gave some documents to security of his medical examinations... I must see them," Bachchan posted.