Meanwhile, three poll officers Baldeo Prasad Yadav, K N Sigh and Satyendra Patel, were reportedly missing after the incident.
On the second phase of polls several other incidents were also reported from the other parts of the districts.
Vehicles of state JD-U minister Dinesh Prasad Kushawaha was attacked by supporters of an Independent candidate Madhavi Chandra in Muzaffarpur district.
In another incident BJP nominee Veena Devi was also attacked, while the minister escaped unhurt, his bodyguard suffered injuries in the attack.
Nearly 48 persons have been detained as part of preventive measures in Samastipur, Muzaffarpur and Sitamarhi districts, official sources said.