The woman, who appeared to be in her forties, went to the Citizen Facilitation Centre of the police headquarters in south Mumbai and demanded to meet Kasab, who is presently lodged in Mumbaiís Arthur Road jail.
The woman spoke with a Punjabi accent and was dressed in traditional attire. She wanted to meet the head of the Crime Branch and said she had come to meet him since she was Kasab's mother, the officer said.
The lady claimed that Kasab had been kidnapped from her custody when he was a child and asked for a DNA test to be done on her to verify her claim.
However, officials sent her off without allowing her to enter the complex but did not record her antecedents, "doubting her mental stability".
"The lady had come here and left after making these claims. She has not made any official application. No official report has been made on the matter," Deputy Commissioner of Police (Headquarters) V M Jadhav said.
If any application or letter had been received from the woman her claims would have been verified, said Jadhav.
Kasab, a resident of Faridkot in Pakistan, was the only terrorist caught alive during the November 26 terror strikes.
Over 180 people were killed in the terror strikes which targetted the historic Chhatrapati Shivaji rail terminus, Chabad House in Colaba and Taj and Trident hotels. Nine other terrorists involved in the attacks were killed by security forces.
Kasab is currently lodged in a high security barrack in the Arthur Road jail and is to face trial along with two alleged Indian Lashkar-e-Taiba (LeT) operatives for their alleged involvement in the terror strikes.
The trial, to be held in a high security court in the jail complex is expected to begin on April 15.