(CNN) -- An Afghan soldier fled after he opened fire on NATO troops, wounding one, military officials said Sunday.
The injured Polish soldier was hospitalized after the Saturday attack in Ghazni province. International forces and Afghan troops are searching for the shooter.
The Afghan National Army soldier shot the victim during an argument, the country's ministry of defense said.
Attacks on NATO troops by Afghan soldiers have escalated in recent months. The Taliban claims responsibility for the attacks and says its members have infiltrated Afghan forces.
In December, an Afghan soldier killed a U.S. troop member and injured two Italians at a shared base. A month before, an Afghan policeman killed five British soldiers in southern Helmand province.
The NATO-led International Security Assistance Force was formed under a U.N. mandate to bolster a secure environment and support the reconstruction of Afghanistan.
NATO took command of the force in 2003. It comprises about 50,000 troops from 42 countries, according to the organization.
Meanwhile, four people were killed and 13 others injured in two roadside bomb blasts in Afghanistan's Kandahar province Sunday, officials said.
The first bomb struck a vehicle belonging to the Demining Agency for Afghanistan as it drove through the Daman district of the province.
When medics arrived to help, a second bomb went off, said a spokesman for the province.
The agency clears mines across southern Afghanistan.
Journalist Matiullah Mati contributed to this report.