The police said two cousins from Teotia's native village hired four attackers and their accomplices to avenge a family member's killing 17 years ago.
Those arrested were identified as Rahul Tyagi (26), Ram Kumar (25), Nishant Singh (25) and Jitendra alias Pope (40). Remaining eight persons involved in the crime were yet to be arrested, a police officer said.
Inspector General of Police (Meerut Zone) Sujeet Pandey told the media here that Manish and Manoj, both cousins, hailed from Teotia's native village Mahrauli with the jurisdiction of Kavi Nagar police station of Ghaziabad.
The officer said both hatched the conspiracy to avenge the murder of Manish's father Suresh Diwan, a Delhi Police Constable killed in 1999 in Shakarpur in Delhi.
Pandey said though Teotia was the main accused and even named in the complaint, the Delhi Police closed the case in 2001 and submitted its final report in the court.
Teotia was a Delhi Police constable but was suspended in 1995. He later left the police force.
The IG said both Manish and Manoj had admitted to hiring shooters from other states for the crime, and added that the seizure of a mobile phone and SIM led to unearthing of the conspiracy.
The police officer said a total of 12 persons were involved in conspiring, carrying out a recce and then shooting at Teotia. Following the arrest of the four persons, the police were looking for the remaining eight involved in the shooting, including main conspirators Manish and Manoj.
"We set up 20 teams comprising Special Task Force officers from Noida, Ghaziabad and Meerut to crack the case. An AK-47 rifle, two pistols, mobile phone, SIM, scooty and a sports utility vehicle have been seized in the case," Pandey said.
On August 11, nearly 100 rounds were fired from automatic weapons at Teotia and his private security guards near Gang Nehar police post under Modi Nagar police station.
Teotia sustained six gunshot injuries. Others injured in the attack were Ram Pal Singh, Ashok Singh, Mohkam Singh Malik, Indra Pal Singh and Vipin.
Teotia had contested the 2012 Uttar Pradesh assembly election on a BJP ticket but lost. He is at present recovering at Noida's Fortis Hospital.
