4 NATO SOLDIERS KILLED; BOSNIAN PRISONERS FREED.

Byline: Srecko Latal Associated Press 

Bosnia's former battlefield foes claimed Sunday they had emptied their jails of all POWs, in a day marred by the deaths of four NATO soldiers and the wounding of a U.S. Army officer by sniper fire.

Three British soldiers were killed when their vehicle hit a mine near Mrkonjic Grad in the northwest. A Swedish soldier died when an armored personnel carrier skidded off a road in the north.

In Ilidza, a Serb-held suburb west of Sarajevo, Lt. Shawn H. Watts was grazed on the neck by a sniper's bullet. The 28-year-old from Greenwood, Miss., returned to duty several hours later.

NATO said it was investigating, but Bosnian Serb army officials in Ilidza said they knew nothing of the shooting.

It was the biggest death toll of any single day of the NATO-led mission since it began Dec. 20. Before Sunday, there were 35 injured and four dead, including a British soldier who killed himself.

Meanwhile, with hundreds of war prisoners released Saturday, it appeared that most of those in captivity before the weekend had been set free.

Croats and Muslims freed about 380 prisoners Saturday at the Sarajevo airport, a neutral site commonly used for such releases. On Sunday, 74 were confirmed released by the Serbs and eight by the Bosnian government.

A Bosnian Serb spokesman said the release of another 74 outside of Sarajevo accounted for all Serb-held POWs.