UN observers caught up in Syria violence
16 May 2012 Last updated at 11:27 BST
UN observers deployed to monitor a ceasefire in Syria, have been caught up in the violence during a visit in Idlib province.
Activists say at least 20 people were killed in the attack.
Unconfirmed reports say security forces opened fire on a funeral procession in the town.
Barbara Plett reports from the United Nations in New York.