Fighting in a disputed border region between Sudan and South Sudan has raised fears the two countries could resume full-blown war.
Here is a look at the two countries' military capabilities according to the International Institute for Strategic Studies report, "Military Balance 2012":
* PERSONNEL: South Sudan has around 140,000 military personnel all of whom are in the army.
* MAIN BATTLE TANKS: The force includes over 110 main battle tanks made up of some T-55 and 110 T-72s.
* ARTILLERY: The military holds 69 pieces of artillery including 24 self-propelled 122mm guns. There are also 15 BM-21 122mm multiple rocket launchers. South Sudan also has more than 30 82mm mortars.
* AIR FORCE: South Sudan has one Beech 1900 light transport aircraft as well as nine Mi-17 multi-role helicopters and one Mi-172 transport helicopter.
* PERSONNEL: Sudan has 109,300 military personnel. Sudan also has a paramilitary force of 17,500, which is the military wing of National Islamic Front.
* ARMY: The country has a regular army of 85,000 and 20,000 conscripts.
* MAIN BATTLE TANKS: Sudan's force has 390 main battle tanks including 20 M-60 A3s and 60 Type-59/Type 59D and 300 T-54/T-55s.
* LIGHT TANKS: It also has 115 light tanks, 70 Type-63 and 45 Type-63. The force also includes 412 armored personnel carriers.
* ARTILLERY: Sudan has 778 pieces of artillery including 20 self-propelled and 123 towed. Sudan has 635 multiple rocket launchers including 477 107mm Type-63's.
* NAVY: Sudan's navy has 1,300 personnel. It has four patrol and coastal combatants and seven amphibious landing craft.
* AIR FORCE: There are 3,000 personnel. Sudan has 61 combat capable aircraft including 23 fighter aircraft consisting of 21 MiG-29SE/ Fulcrum and two MiG-29SE/ Fulcrum UB.
There are 26 attack aircraft including 15 A-5 Fantans and nine Su 25 Frogfoot. Sudan also has 23 transport aircraft.
* HELICOPTERS: 29 Attack helicopters including 15 Mi-24 Hind and about five multiple-role Mi-17 Hip H helicopters.
* AIR DEFENCE: 90 towed S-75 Dvina Surface to Air Missiles.
Sources: Reuters/IIS Military Balance 2012
(Reporting by David Cutler, London Editorial Reference Unit)