The middle-aged resident of West Bengal's Hooghly district feels the sole surviving terrorist in the attack should have been given a "barbaric death".
"I would be lying if I said I am happy that Kasab, who was responsible for my mother's and many others death, has been hanged. He should have been given an excruciating and barbaric death," said Chatterjee before breaking down.
"The station complex was scattered with limbs, blood and human parts. There was wailing all around and the man responsible for this gory act was only hanged. He deserved a more painful death," Chatterjee told reporters.
His mother Meera, waiting at Chhatrapati Shivaji Terminus (CST) to catch a train home, was one of the 166 victims of the three day carnage carried out by Kasab and nine of his associates.
Meera Chatterjee, 66, from Singur, had gone to the country's commercial capital to be with her son who had just lost his job and was in a state of serious depression.
A terrorist walked up to Chatterjee and shot her at point blank range.
Her two sons - Ardhendu and Purnendu - had gone to get some food for their mother at the platform and escaped the terrorist's bullets by minutes. They heard the gunshots but could not realise that it was their mother who was killed in the firing.
When both the brothers ran back they could only find bullet marks and bloodstains all over the place. Their search for their mother had ended at a nearby hospital's morgue two hours later.
He, however, said justice has been done but demanded a similar fate for other terrorists.
"The hand which had touched my mother has been broken. Though it came late but still justice has been done. But people like me who have lost their dear ones in terror attacks would be happy if all terrorists are terminated," added Chatterjee.
Pakistani national Kasab was hanged in a Pune jail at 7.30 a.m. on Wednesday, after his mercy plea was rejected by President Pranab Mukherjee earlier this month.
Kasab -- who was barely 21 when he carried out the brutal attack -- was sentenced to death on four counts and to life sentence on five counts on charges including murder, waging a war on India and possessing weapons.
His execution has been hailed by people across the country.