11.   One incursion provoked Serb gunfire, damaging a U.N. vehicle but causing no casualties, the agency said.

12.   One such incursion provoked Serb gunfire that damaged a U.N. vehicle but caused no casualties.

13.   Serb gunfire and threats have crippled the U.N. aid airlift into beseiged Sarajevo.

14.   Serb gunfire has shut the airport down.

15.   Serb gunfire and threats have crippled the U.N. aid airlift that kept Sarajevo alive for nearly three years.

16.   Some tram service was restored last year, but the cars are convenient targets for Serb gunfire -- dozens of people on them have been killed or wounded.

17.   The airport route was closed in July by threat of Serb gunfire.

18.   The Bosnian-held Mount Igman route is under constant Serb gunfire.

19.   The route was closed in July by threat of Serb gunfire.

20.   The road, a target of Serb gunfire, had been closed since July.