Police search for motives in Serbian gunman rampage that killed 13 people in quiet village

The Serbian flag flies at half-staff on the Serbian Parliament building, Wednesday, April 10, 2013, in Belgrade, Serbia, in honor of six men, six women and a child dead in the village of Velika Ivanca. A 60-year old veteran on Tuesday gunned down 13 people in Serbia, including his mother, his son and a two-year-old cousin before shooting himself and his wife. (AP Photo/Darko Vojinovic) (The Associated Press)

This undated photo provided by Stanica Kostadinovic shows Ljubisa Bogdanovic who, according to police, gunned down 13 people, including a baby, in a house-to-house rampage in the quiet Serbian village of Velika Ivanca Tuesday, April 9, 2013. Belgrade emergency hospital spokeswoman Nada Macura said Bogdanovic, 60, used a handgun in the shooting spree at five houses, then tried to kill himself and his wife. (AP Photo/Courtesy of Stanica Kostadinovic) (The Associated Press)

Serbia is in mourning as police search for possible motives in the Balkan country's worst peacetime shooting massacre, which left 13 people in a sleepy village dead.

Police say a 60-year-old veteran went on a pre-dawn, house-to-house rampage Tuesday in a village near Belgrade, including killing his mother, his son and a two-year-old cousin before shooting himself and his wife. The two are in critical condition in a Belgrade hospital.

Police say they have no clue as to why the suspect, identified as Ljubisa Bogdanovic, went on the rampage. They know that he fought in one of the bloodiest sieges of the Balkan wars in the 1990s, and lost his job a year ago.

Police chief Milorad Veljovic said Wednesday the suspect's injured wife could provide the motive.