22 PALESTINIANS KILLED IN BEIRUT
Right-wing Lebanese Phalangist party gunmen on Apr 13 open fire on bus filled with Palestinian militants, killing 22; incident occurs during opening of Christian eh by followers of Pierre Gemayel, leader of Phalangist party, which opposes Palestinian guerrilla presence in Lebanon; bus reptdly was coming from rally organized by guerrilla group to celebrate 1st anniversary of guerrilla attack on Israeli town of Qiryat Shemona; Phalangist party member is later killed in same neighborhood by shots fired from passing auto; shooting is reptd near 2 Palestinian camps in Beirut; PLO calls emergency meeting; PLO chmn Yasir Arafat sends messages to Arab leaders accusing party of being 'used by imperialism and Zionism' to promote crisis between Palestinians and Lebanese pol forces (M)
