Sonu Dariyapur, who was carrying a reward of Rs 5 lakh, was arrested this morning from Narela, the police said.
In a shootout on April 30, gangster Monu Dariyapur, his personal security officers, Delhi Police ASI Vijay Kumar and Constable Kuldeep, and two others, Arun Shastri and Yogesh, were attacked in outer Delhi's Mianwali Nagar.
Some armed men had fired at their car leading to the deaths of Monu, Mr Kumar and Mr Shastri and injuring the other two. Monu was previously a member of Sonu Dariyapur's gang. Both of them were friends but the relationship got bitter after Monu married Sonu's cousin, due to which the latter decided to kill him.
In 2006, Sonu along with his other associates had also fired at the car carrying Monu and his wife. In this firing, driver of the car was killed and the two critically injured.
After that incident, they were provided security by the Delhi Police.
Sonu had hatched a conspiracy with his gang members to kill Monu and they succeeded in killing him on April 30.