The police in Kaduna has asked Senator Sani to appear at the Command Headquarters on April 30 for questioning.
Premium Times obtained a copy of the letter the state police commissioner, Austin Iwar, addressed to Sani, who represent APC-Kaduna Central in the Senate.
In the letter, Iwar asked the lawmaker to appear on April 30 at the Command Headquarters in Kaduna for questioning.
"This is in connection with a case of criminal conspiracy and culpable homicide transferred to this office by 1 Division, Nigerian Army, Kaduna, alongside with exhibit audio CD in which your name was mentioned by the principal suspect," Iwar said in the letter.
The state police boss concluded that Sani's presence for questioning will "enable us fairly and timely conclude investigation into the matter."
The letter was said to have been sent to the Senator through the Clerk of the National Assembly - a copy of it was forwarded to Senate President Bukola Saraki.
The police, however, was not specific about the homicide case allegedly involving Sani.
It is believed that this may be connected to recent violent confrontations between supporters of Sani and those of the Kaduna state governor, Nasir el-Rufai.
The crisis also broke the APC chapter in the state into two factions.
But the police commissioner said the murder case is not politically-motivated.
"A case was transferred to me and I am handling the case," Iwar told Premium Times.
"The matter is currently under investigation and we don’t think we have reached a stage yet where we could inform the public about it," he added.
According to him, if Sani honours the police invitation, he would not be detained. He said the command would have arrested him if that is the intention.
Reacting to the police action, the lawmaker accused el-Rufai of instigating the police against him.
Sani said he had been informed that the Kaduna government was plotting to frame him for murder.
"There is an attempt to frame me up with a murder case by the Kaduna State Government using the police. A letter has been written from the office of the Commissioner of Police office but it has not been delivered to us", the lawmaker said.
He added that the murder case is already before a court of law, alleging that el-Rufai wrote the judge in charge of the case to express interest in the case.
Attempts to get a response from the spokesperson for the Kaduna state governor, Samuel Aruwan, was abortive as he declined to comment on the matter.