Tensions along the Assam-Mizoram border arose again on Sunday over the construction of a bridge, PTI reported.

The Mizoram police filed a case against Assam police officers for allegedly stealing building material from the project site, while Assam claimed that the bridge was being built in its territory, the Hindustan Times reported.

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

The incident took place less than a month after violence erupted along the 164.6-km-long border shared by the two states. Five Assam police officers were killed in the clash. On August 5, Assam and Mizoram signed a joint declaration to find a lasting solution to the border conflict.

The deputy commissioner of Kolasib in Mizoram, H Lalthlangliana, told PTI on Sunday that the bridge was being built in Zophai area near the state’s Bairabi town. It is meant to connect a road to a field belonging to the state’s former Chief Minister C Chhunga.

The area borders Assam’s Hailakandi district. Lalthlangliana alleged that on Friday, Assam police officers entered Mizoram’s territory and stole iron rods and other materials from the construction project site, according to PTI.

Lalthlangliana wrote to his counterpart in Hailakandi, saying that the construction of the bridge within Mizoram’s territory should not be connected to the border dispute. “However, government servant committing an act that can be interpreted as theft towards government property is very disappointing and considered very serious,” he added.

Lalthlangliana also accused the Assam police of creating problems for the workers at the project site, the Hindustan Times reported. “A police case against theft of construction materials has been filed against them at Bairabi police station,” the officer added.

On the other hand, the Assam police alleged that Mizoram was building the bridge in Assam’s territory without permission.

“The Mizoram authorities were constructing a bridge over a ‘nullah’ [stream] at Kachurthal, which borders Mizoram on one side and Assam on the other,” Hailakandi Superintendent of Police Gaurav Upadhyay said, according to the Hindustan Times.

He added: “Since the construction was being done on Assam’s territory, necessary authorisation from our side should have been taken. But the Mizoram side didn’t do that.”

Upadhyay described Mizoram’s accusations against the Assam police as “concocted, baseless, malafide and devoid of any facts”.