"We have registered a case under section 153A , 295A, 504, 506 of IPC", said Manoj Kumar, SSP, who arrested Imran.
A video of Imran threatening to "chop Narendra Modi to pieces" had gone viral on the web recently.
The 40-year-old, who is contesting from Saharanpur in western Uttar Pradesh, faces criminal charges for his hate speech against the BJP's Prime Ministerial candidate. However, he now argues that his words were misinterpreted.
"I meant that I would teach him a lesson," he told NDTV.
An FIR filed against him accuses him of violating the election code of conduct. The police say they received the video CD on Thursday.
According to Masood,the video is eight months old, when he was with the Samajwadi Party.
Rahul's Saharanpur rally
Congress vice president Rahul Gandhi is set to hold a rally in Saharanpur on Saturday. The Congress has condemned Imran's remarks but has not cancelled the rally. Senior party leader Digvijaya Singh, however, said the comments should not go unpunished.
In the video, Masood is seen saying, "I am a man of the street, ready to give my life for my people. I am neither afraid of death or of killing. He thinks this is Gujarat. There are only 4% Muslims in Gujarat. There are 42% Muslims here."
In his speech, Masood also Modi, who is contesting from varanasi, against "turning Uttar Pradesh into Gujarat."