The NDMC leader, however, termed the accusation as "baseless".
Mohammed Moin Khan, a lawyer and an assistant legal advisor with NDMC, was shot dead a day before he was scheduled to pass the final order on the lease terms of hotel 'The Connaught' which was functioning on a property leased by the civic body.
Police had yesterday arrested the owner of hotel, Ramesh Kakkar, and five others in connection with Khan's murder.
Tanwar had written a letter to Lt Governor Najeeb Jung, alleging Khan was acting in a "biased" manner in favour of NDMC and had demanded that he be transfered, AAP's Delhi unit convenor Dilip Pandey said.
Also Read
"Tanwar should immediately be sacked from the post of NDMC Vice-Chairman, arrested and interrogated," Pandey said.
AAP MLA Surinder Singh said, "Khan had come to my office on May 2 and said Tanwar threatened him with dire consequences if he did not set aside the matter."
"Khan had come to me on May 9, seeking my recommendation to book the NDMC hall at Moti Bagh for his daughter's wedding in November. The hall was already booked. And if Singh says that I threatened Khan then why is he saying this now?"
Tanwar, however, admitted writing the letter to the LG, but said he did not know Kakkar.
"Around 200-300 people come to meet me everyday. Some representatives of the hotel had also come to meet me. Since the LG is the competent authority, I wrote a letter to him demanding a free and fair probe into the issue," Tanwar said.