Months of simmering tensions between Cambodia and Thailand exploded into armed conflict on Thursday, including the deployment of a Thai F-16 fighter jet, in the heaviest fighting between the Southeast Asian neighbours in over a decade.

Here is a look at the defence forces and arsenals of two countries, according to data from the London-based International Institute for Strategic Studies:

BUDGETS AND GROUND PERSONNEL

Cambodia had a defence budget of $1.3 billion in 2024 and 124,300 active military personnel. The armed forces were established in 1993 from the merger of the country's former Communist military and two other resistance armies.

Of this, the Cambodian army is the largest force, with some 75,000 soldiers, backed by more than 200 battle tanks and around 480 pieces of artillery.

Thailand, which the US classifies as a major non-NATO ally, has a large, well-funded military, with a defence budget of $5.73 billion in 2024 and over 360,000 active armed forces personnel.

The Thai army has a total of 245,000 personnel, including an estimated 115,000 conscripts, around 400 battle tanks, over 1,200 armoured personnel carriers and some 2,600 artillery weapons.

The army has its own fleet of aircraft, comprising passenger planes, helicopters such as dozens of U.S.-made Black Hawks, and unmanned aerial vehicles.

AIR FORCES

Cambodia's air force has 1,500 personnel, with a relatively small fleet of aircraft, including 10 transport planes and 10 transport helicopters.

It doesn't possess any fighter aircraft but has 16 multi- role helicopters, including six Soviet-era Mi-17s and 10 Chinese Z-9s.

Thailand has one of the best equipped and trained air forces in Southeast Asia, with an estimated 46,000 personnel, 112 combat capable aircraft, including 28 F-16s and 11 Swedish Gripen fighter jets, and dozens of helicopters.

NAVIES

The Cambodian navy has an estimated 2,800 personnel, including 1,500 naval infantry, with 13 patrol and coastal combat vessels and one amphibious landing craft.

Thailand's navy is much larger, with nearly 70,000 personnel, comprising naval aviation, marines, coastal defence and conscripts.

It has one aircraft carrier, seven frigates, and 68 patrol and coastal combat vessels. The Thai fleet also contains a handful of amphibious and landing ships capable of holding hundreds of troops each and 14 smaller landing craft.

Thailand's naval aviation division has its own fleet of aircraft, including helicopters and UAVs, besides a marine corps that has 23,000 personnel, backed by dozens of armed fighting vehicles.