Chetan Chaudhary was caught with the weapon allegedly used in the crime.
Sacked Railway Protection Force constable Chetansinh Chaudhary, who is accused of shooting dead his colleague and three passengers on board a train last month, does not remember anything "about the incident, his arrest or custody", his lawyer said on Thursday.
Lawyer Amit Mishra, who met his client in jail in neighbouring Thane during the day to discuss the case, told PTI the latter did not answer any of his questions.
"He has said he does not remember anything about the incident, his arrest or his custody," mr Mishra said, adding that Chaudhary's "mental condition is bad" due to which personnel "monitoring and protecting him in jail custody are also worried".
The personnel accompanying Chaudhary have said his behaviour is "very unusual and he is in deep shock" and that he just eats "occasionally", the lawyer claimed.
Responding to a question, the accused said he does not know about his caste but only that his name was Chetan and that he was Hindu, Mr Mishra informed.
On July 31, Chaudhary allegedly shot dead his superior Tikaram Meena and three passengers, identified as Abdul Kadar Mohamed Hussain Bhanpurawala, Sayyad Saifuddin and Asgar Abbas Shaikh, on board the Jaipur Mumbai Central Superfast Express near Palghar station.
Chaudhary was caught with the weapon allegedly used in the crime and was charged with murder, kidnapping as well as Indian Penal Code section 153A for promoting enmity between different groups on grounds of religion etc.
On Monday, he was dismissed from service through an order issued by the RPF's senior divisional security commissioner.
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