The gunfight at Dobasipara area took place after suspected ANVC-B rebels lobbed a crude bomb at a petrol pump in Hawakhana area in Tura, the district headquarters of West Garo Hills.
Though there were no casualities in the explosion, two vehicles were damaged.
The gunfight began when rebels holed up in the area opened fire at Special Weapons and Tactics (SWAT) commandos.
Four rebels were killed in the shootout, district police chief Mukesh Kumar Singh told IANS.
A combing operation is on to nab the escaped rebels.
Another senior police official said a huge cache of arms and ammunition, including explosives, has been recovered from the shootout site.
“A bomb squad has cordoned off the entire area to defuse the explosives,” he said.
The ANVC-B is a splinter group of the ANVC, which has been observing a tripartite ceasefire with the central and Meghalaya governments for nine years.