Indian media is not disclosing names of the 2 communities, but Singhs have reported that its between Sikhs and Muslims, and that it started after Muslims attacked a Gurdwara Sahib which the Sikhs defended. Just recently Guru Sahib's saroop's beadbi was also done and it was verified that the person was a Muslim.
[
www.indianexpress.com]
[
zeenews.india.com]
ਸਤਿਗੁਰਬਚਨਕਮਾਵਣੇਸਚਾਏਹੁਵੀਚਾਰੁ॥