Four of the eight accused have been nabbed for blackening Sunil Kumar Rai's face during a protest on Monday, police said.
Jay Dixit, Pawan Reddy, Nitin Kumar and Ravi Pawar were arrested under section 323 (voluntarily causing hurt), 353 (assault), 504 (intentional insult) and 506 (criminal intimidation) of IPC, SHO Sahibabad Rashid Ali said.
The other four accused will be nabbed soon, he added.
The GMC employees who were protesting against the Monday's incident brought their strike to a halt and returned to their work after three days, president of GMC Employees Union Harendra Naagar said.
During their protest, some GMC officials tried to disperse them by altercation, Dixit, secretary of Shalimar Garden Sudhar Samiti, had alleged.
One of the residents splashed ink to blacken the face of Rai and manhandled him.
After the incident, a scuffle took place between the residents and GMC staff.
