Cambodian Prime Minister Hun Manet accused Thailand on Thursday of barring civilians from returning to their homes on the disputed border between the two countries.

It comes a day after Thai police fired tear gas and rubber bullets at Cambodian protesters in a disputed borer village.

The Cambodian PM sent a formal letter on Tueday to UN Secretary-General Antonio Guterres which was released on Thursday.

In the letter, he accused Thai forces of having "widened the conflict zone by erecting barbed wire and barricades," and "forcibly" evicting Cambodian civilians from their "long-settled lands" in two border villages in northwestern Banteay Meanchey province since last month.

"Twenty-five families have already been blocked from their homes and fields," Hun Manet wrote, saying a Thai military spokesperson had threatened more evictions, "potentially affecting hundreds of households comprised of about a thousand inhabitants."

Some 23 Cambodians were injured in Wednesday's incident, according to Cambodian authorities.

The clash took place at a disputed border town that Thailand claims as part of Ban Nong Ya Kew village in southeastern Sa Kaeo province, but which Cambodia says is part of Prey Chan village in its northwestern Bantheay Meanchey province.

The Southeast Asian neighbors had just recently reached a ceasefire in late July, after five days of clashes along the border left at least 43 people dead.

In response, the Thai army said the evicted Cambodian residents had "illegally occupied" Thai territory.

Thai army spokesperson Winthai Suvaree said in a statement accused Cambodian military personnel of failing to intervene on Wednesday as Cambodian villagers "carried long wooden sticks as makeshift weapons, showing intent to harm Thai officials and breach Thai barriers."

Thailand's army said it had to use force to respond to provocation from some 200 Cambodian protesters, some of whom dismantled Thai defensive barriers, threw sticks and stones and fired slingshots at Thai officials.

The clashes between Cambodia and Thailand in July forced 300,000 people to flee their homes along the border.

The two nations agreed on an "immediate and unconditional" truce, after a mediation meeting in Malaysia, the current chair of the Association of Southeast Asian Nations (ASEAN).

But just hours after the ceasefire came into effect, the Thai army reported violations by Cambodian forces in multiple areas -- claims that were dismissed by Cambodia's Defense Ministry.

Since then, both sides have since traded accusations of ceasefire violations.

Hun Manet warned that Thailand's "unilateral actions that risk escalating tensions and widening the conflict."

Cambodia accuses Thai army of forced civilian evictions