The National Human Rights Commission has issued notices to the central government, Assam and Mizoram in connection with the clashes at the border between the two northeastern states, The Indian Express reported on Monday.

The NHRC has issued the notices after it got a complaint by Mohammed Injamul Haque, a resident of Assam’s Kamrup district. Haque has alleged a mob along with the Mizoram Police had attacked senior police officers and district officials of Assam.

On July 26, violence had erupted along the state border after reports of firing and clashes between the police of the two states emerged.

During the clashes, five Assam Police officers died. The Mizoram government claimed that around 200 Assam Police personnel had crossed a duty post manned by the Central Reserve Police Force and state police in Vairengte town in Kolasib district.

The human rights body on Sunday issued the notices to the Union home secretary and the chief secretaries of Assam and Mizoram, and has sought their reports on the matter within four weeks. It said that the facts of the case were disturbing.

“The allegations made in the complaint are serious in nature involving deaths and injuries to the public servants,” PTI quoted the NHRC as saying. “The case therefore involves grave violation of human rights of the deceased and injured. Such types of cases are viewed very seriously by the commission.”

Haque is a 21-year-old law student in Guwahati. He filed the complaint on July 30, four days after the incident.

“I have no personal links to the case but I filed the complaint purely on humanitarian grounds,” he said, according to The Indian Express. “There should be some legal action…considering so many officers got killed.”

The NHRC issued the notices on a day when tensions escalated again along the state boundary, this time over the construction of a bridge.

The Mizoram police filed a case against Assam police officers for allegedly stealing building material from the project site. On the other hand, Assam claimed that the bridge was being built within its territory.

Mizoram withdrew the case after an official returned the construction materials, The New Indian Express reported.

Assam and Mizoram share a 164.6-km-long border, which has long been a cause of dispute.

On August 5, Assam and Mizoram signed a joint declaration to find a lasting solution to the border conflict.