Vladimir Krapivin's meaty hands form a bowl under his collection of shell fragments, proffered as evidence of the harassment he and other Russian policemen endure as they wait to play their part in a stalled U.N. airlift for northern Bosnia's war victims.
"They shoot at us all the time," says the exasperated Russian, deployed to the U.N.-controlled airport here to inspect aid cargo for contraband. "They get drunk, and they shoot at anything that moves."
Krapivin is not grousing about Bosnian government forces, who object to the assignment of Russian civilian policemen to the airlift for fear they will work on behalf of their Slavic Christian brothers, the rebel Serbs.
It was Bosnian Serb leader Radovan Karadzic who insisted on the deployment of 80 Russian police monitors as a condition for consenting to the humanitarian relief flights that will mostly benefit Muslim refugees.
Instead, in the boomerang logic of Balkan politics, it is the Serbs who are shooting at the Russians, just as they target other U.N. soldiers and policemen.
The artillery shells and mortars are random expressions of wrath at the U.N. Protection Force, which last month halted a deadly Serbian offensive against the eastern city of Gorazde.
While some of the 400 Russian troops deployed to Serb-held areas around the capital of Sarajevo say they believe that the globally condemned Serbian nationalists have been getting an unfair rap, the first four policemen assigned to Tuzla's airport have taken pains to appear impartial.
"We are not here as Russians but as members of UNPROFOR," insists Yevgeny Cherenkov, jutting his chin toward the sky-blue U.N. emblem stitched to his sleeve.
That internationalist pose has riled the Serbian gunmen, who have the airport in their sights from less than five miles away.
The three-week Serbian offensive against Gorazde that captured nearly half of the U.N.-designated safe area and killed hundreds of Muslim civilians discredited the rebels in the eyes of the outside world, including their traditional allies in Russia.
Russia's deputy foreign minister and special Balkans envoy, Vitaly S. Churkin, complained after shuttling among Serbian leaders in a failed attempt to head off the Gorazde debacle that he had never been lied to so much in his life.
Russian troops guarding impounded Serbian weapons in the Sarajevo suburb of Hreso were taken captive by angry rebels after token North Atlantic Treaty Organization air strikes against Serbs attacking Gorazde, and a Ukrainian soldier was shot to death in Serb-held territory there last week.
Whatever sympathies the Slavic peacekeepers might have had for the Serbs seem to be waning as they are exposed to indiscriminate acts of retaliation.
But the isolation the Serbian nationalists have brought on themselves since Gorazde may be dawning on them, because signs have emerged in the last few days that they want to repair relations with the U.N. mission.
Bosnia-Herzegovina's Muslim-led government had refused to resume negotiations on an ethnic partitioning plan proposed by the United States, Russia and Western Europe, complaining that the Serbs were blatantly violating a NATO ultimatum to withdraw from a 1.9-mile radius around Gorazde.
U.N. officers in Gorazde have confirmed that at least 150 Serbian soldiers remained deployed inside the exclusion zone after an April 21 deadline, having switched from army camouflage to blue jumpsuits to masquerade as civilian policemen.
A senior Serbian military official, rebel Chief of Staff Manojlo Milovanovic, promised U.N. officials that all armed Serbian forces would be withdrawn from the Gorazde safe area by 6 p.m. Sunday.
The pledge raised hopes among U.N. officials that the rebels want to restart peace talks.
U.N. monitors reported no signs of an impending withdrawal by the Serbs on Sunday afternoon, U.N. spokesman Maj. Rob Annink said. But he noted that communications with the region were poor and that compliance could be achieved swiftly if the rebels are sincere.