Mizoram Home Minister Lalchamliana, in an official statement, asserted that it was Assam Police who opened fire first after forcibly crossing a duty post manned by CRPF personnel and "overran a duty post manned by one section of Mizoram police personnel" at Varirengte.
He reiterated that Assam police was "adamant" and not willing to discuss the issue.
He also said that Assam Police damaged several vehicles that were travelling along the National Highway between Vairengte and Lailapur.
Upon learning of the "arson" committed by Assam Police, residents of Vairengte town, Kolasib District proceeded to the site to inquire.
"These unarmed civilians were assaulted by Assam Police by lathi charging them and firing tear gas, thereby causing injuries to several civilians," he said.
Meanwhile, SP of Kolasib and an Executive Magistrate went to meet them and try to resolve the issue. However, "Assam side were adamant and unwilling to discuss the issue," he said.
In a matter of minutes, a volley of tear gas canisters and grenades were launched at Mizoram Police followed by firing from Assam side at around 4:50 p.m, he said.
Mizoram Police had to respond spontaneously by firing back at Assam Police inspite of the fact that SP, Kolasib District was still inside CRPF duty camp negotiating with the Assam Police authorities, he said.
"It all started with the Assam Police aggression into the duty camps of CRPF and Mizoram Police near Vairengte Auto-Rickshaw stand," he asserted.
He also called the entire development "quite unfortunate".
Only after intervention Union Home Minister Amit Shah, Assam Police withdrew from the place and the duty post was handed back to CRPF personnel, he said.
"The Government of Mizoram strongly condemns the unjustified act of the Government of Assam in this intrusion and aggression into the territory of Mizoram," his statement further read.
"The Government of Mizoram desires that the inter-state border issue with Assam be resolved in an atmosphere of peace and understanding. Accordingly, we call upon the State of Assam to create congenial environment for peaceful resolution of the dispute," it added.