Bhojpur District Magistrate Birendra Prasad Yadav told PTI the clashes took place at the Piro Bazar near here yesterday and Internet services were suspended to stop rumour-mongering.
The Internet services are likely to be restored by Wednesday morning, he said.
The trouble erupted when the Muharram procession diverted from its pre-determined route, he said.
This led to a stone-pelting between people of the two communities which left more than 12 injured. Some two-wheelers and a four-wheeler were also set ablaze, he said.
Shahabad DIG is camping in the area and the situation is under control, the DM said.
The Piro Bazar had witnessed clashes last year also during Durga idol immersion and Internet services were suspended for five days. Four people were arrested in connection with the incident.