Police, however, charged the MLA with not cooperating with them and said it may approach a court to seek his arrest warrant.
Yadav, accompanied by AAP's Punjab convener Sucha Singh Chhotepur and AAP leader Himmat Singh Shergill, appeared before the Sangrur police for the second time to join the investigation. He was questioned for more than eight hours, officials said. Yadav was earlier questioned for five hours on July 5.
After coming out of the Crime Investigation Agency (CIA) wing of Sangrur police, Yadav alleged that police misbehaved with him during questioning.
"I cooperated with police during questioning but they misbehaved with me. They asked me improper questions and in an indecent way. I have already said that I am available for investigation whenever police calls me," Yadav said.
Denying Yadav's allegation, Sangrur SSP Pritpal Singh Thind said "It is completely wrong. It is a serious case which we are investigating. There is nothing political in it."
"He did not cooperate with us. He could not give replies to our questions. Today his answers were different from what he had given to the same questions asked earlier," the SSP said.
Asked if police sees any role of the MLA in Malerkotla incident, he said, "from questioning, so far, I feel that he (Yadav) was involved."
Asked whether police will arrest the AAP MLA, the SSP said a decision regarding his arrest or calling him again for investigation will be taken in a day or two.
"We are investigating the matter and we are collecting evidence which will be presented in a court to seek his arrest warrant. Or we may also call him again to join investigation.
A decision regarding what course of action we adopt will be taken in a day or two," he said.
AAP MLA had claimed that he was deliberately dragged into the case as part of a political conspiracy.
"I will cooperate with the police during investigation all the time," Yadav said.
Yadav had been booked under relevant sections of the IPC after one of the accused Vijay Kumar, arrested in June 24 Malerkotla sacrilege incident, claimed that he had done at the behest of AAP MLA.