A man identified as Ljubisa Bogdanovic, 60, went on a shooting rampage that killed 13 people, including his mother, son and a two-year-old child, in a small town in central Serbia, Reuters reports.
Bogdanovic also shot his wife and tried to take his own life. Both are in critical condition at a hospital in central Belgrade, the New York Times reports.
"We've never had such a tragedy in Serbia, and we have to find out what drove this man to kill so many people as they slept," police chief Milorad Veljovic said to the media.
Police say the killings took place between 5 a.m. and 5:30 a.m. The massacre started when Bogdanovic shot his 42-year-old son in the head in his home. He then went from house to house, killing his neighbors and relatives, the New York Times reports.
Bogdanovic would have likely continued killing but turned the gun on himself when he saw a police patrol car approaching, Reuters reports.
"If they didn't stop him, he would have wiped us all out," Milovan Konstantinovic, a neighbor, told the AP.
Police say Bogdanovic is a veteran of the Balkan war, where he fought in Croatia during the collapse of former Yugoslavia, and he has a firearms permit, Reuters reports. He used a semi-automatic 9-mm pistol in the shootings, according to the news outlet.
Despite the large amount of weapons left over from the war in Serbia, shootings are rare in the central European country, the AP reports.
"He's a good man, everyone would open their doors to him, he helped everyone in the neighborhood," Konstantinovic told Reuters. "Something must have snapped in his head."