Prayagraj/New Delhi | A letter written by Atiq Ahmad two weeks before his murder with instructions to send it to the Uttar Pradesh chief minister and the chief justice of India in case of his death is being dispatched to them, his lawyer said on Tuesday.

"That letter in a sealed envelope is neither with me nor sent by me. It is kept somewhere else and being sent by some other person. I don't know the contents of the letter," gangster-politician's lawyer Vijay Mishra said.

In a related development, the Supreme Court on Tuesday agreed to hear on April 24 a plea seeking an independent probe into the killing of Ahmad and his brother Ashraf in Prayagraj.

Ahmad (60) and Ashraf were shot dead at point-blank range by three men posing as journalists on Saturday night while police personnel were escorting the two brothers to a hospital in Prayagraj for a check-up.

"Atiq Ahmad had said that if there was any mishap or if he was murdered, the letter in the sealed envelope should be sent to the chief justice of India and Uttar Pradesh chief minister," Mishra told PTI.

The brothers, both jailed in Prayagraj, were in handcuffs when they were killed in full view of camera crews. They were brought to Prayagraj from Gujarat and Bareilly prisons for interrogation in connection with the killing of Umesh Pal and his two police security guards in February this year.

Ahmad had moved the Supreme Court for protection, claiming that he and his family have been falsely implicated in the Umesh Pal murder case and he might be killed in a fake encounter by the Uttar Pradesh Police.

On Tuesday, an apex court bench headed by Chief Justice D Y Chandrachud took note of the submissions of advocate Vishal Tiwari who mentioned the matter seeking urgent hearing. The plea has also sought an inquiry into the 183 encounters that have taken place in Uttar Pradesh since 2017.

The plea sought the setting up of an independent expert committee to probe the killing of Ahmad and Ashraf.

"Issue guidelines/directions to safeguard the rule of law by constituting an independent expert committee under the chairmanship of a former Supreme Court justice to inquire into the 183 encounters which had occurred since 2017 as stated by Uttar Pradesh Special Director General of Police (Law and Order) and also to inquire into the police custody murder of Atiq and Ashraf," it said.

Referring to Ahmad's killing, the plea said that "such actions by police are a severe threat to democracy and rule of law and lead to a police state".

Meanwhile, a crude bomb was hurled in a bylane near the residence of one of the lawyers of the slain gangster-politician on Tuesday, police said.

There was no immediate report of any casualty in the explosion that occurred at around 2.30 pm in Katra locality in Prayagraj, they said.

SHO of Kernalganj police station Ram Mohan Rai claimed Ahmad's lawyer Dayashankar Mishra was not the target and the incident was a fallout of personal enmity between two youths.

However, the lawyer claimed that it was an attempt "to create fear and terror".

Meanwhile, internet services have resumed in Prayagraj after remaining suspended for two days in the wake of killing of Atiq Ahmad and his brother Ashraf, officials said Tuesday. Internet services were suspended by authorities on Sunday.