Salim Alvi, who belongs to Bulandshahr, recorded his statement before the Delhi crime branch, which is investigating the case, claiming that Tomar was hit with a stone by someone and he fell.
His statement contradicts the version given by journalism student Yogendra and his friend Paoline that they saw the 47-year-old constable collapsing while he was following protesters at India Gate on December 23 evening. They claimed that Tomar was not attacked and there were no injuries.
India Gate was the venue of protests against the gang-rape and brutal assault of a 23-year-old girl in a moving bus in south Delhi on December 16.
Yogendra also recorded his statement on Thursday.
A controversy has erupted over the cause of death of Tomar during the violent demonstrations on the gang-rape issue with eyewitnesses and a government hospital claiming there were no injuries on his person while the post-mortem report contradicted these versions.
Police sources said they have call record details, which show that Alvi was at India Gate on December 16.
Before recording his statement, Alvi said, "When the police was going back after lathicharge, Tomar, whose name I got to know later, was a little behind. Someone hit him with a stone and he fell down. After that six-seven people attacked him."
"Three-four people had no caps, four-five people were wearing Aam Aadmi Party caps. When he died I was compelled to come out and say if we were demanding justice for the girl then why not for a policeman or a journalist. So we should tell the truth," he added.
Rejecting the claims, the AAP said the guilty should be punished but there should be a fair investigation. They also sought to question Alvi's credibility.
"Alvi had earlier demanded that (the undivided) IAC should reduce the petrol prices. We had told him we cannot do this as we do not have that power. Later, he sat on a fast in front of Arvind Kejriwal's house....He also tried self immolation at Ramdev and Anna Hazare's joint agitation," AAP leader Manish Sisodia said.
Alvi, who claimed to be a friend of Fiza Mohammed who allegedly committed suicide, had told the Punjab police that she was facing threats from her estranged husband's politician brother.
Yogendra said he appeared before the Delhi police crime branch officials on Thursday afternoon following a notice sent to him by the police asking him to join the probe. "I am under no pressure. I was asked to come here. I will say what I have been saying," Yogendra told reporters.
Police sent notices to Yogendra and Paoline in connection with the investigations in the case. Ram Manohar Lohia Hospital's Medical Superintendent Dr T S Sidhu has also been asked to join the probe after he said Tomar did not suffer any external or internal injury.
The Delhi police had on Wednesday released excerpts of report of the post-mortem done by a board of doctors in the government-run RML Hospital, which said that he died after a cardiac arrest following injuries to neck and chest produced by "blunt force impact".
However, Yogendra and Paoline had claimed that they did not spot any injuries on his person when they tried to revive him after he collapsed near India Gate.
Yogendra and Paoline, who had rushed Tomar to the hospital, had said Tomar fell down on his own. "The truth is that he was not injured at that time. According to doctors too, no injuries were found that caused his death," Yogendra said, adding he had never been associated with any party or organisation.