A joint team of the National Investigation Agency (NIA) and the UP Police was fired upon and pelted with stones by a mob on December 3 when it was carrying out searches in Ghaziabad to apprehend Malook.
The NIA is probing the killing of RSS leader Ravinder Gosain in Ludhiana.
According to Ghaziabad Senior Superintendent of Police (SSP) H N Singh, a team of Bhojpur police arrested Malook from the Delhi-UP border this morning and recovered a country-made pistol and three live cartridges from his possession.
In connection with the attack on the NIA-police team, the Bhojpur police lodged an FIR against Malook, Naushad, Shahzad, Rahees, Naubahar, Mustkeem and Trikat, and 50 unidentified men and women.
So far, police have arrested five people -- Malook, Nazir, Yusuf, Khalid and Naubahar, the SSP said.