A car belonging to UN monitors in Syria has been damaged by an explosion in the central town of Khan Sheikhoun.
None of the observer team was hurt, according to one of the members. But activists say Syrian security forces opened fire on a crowd during the visit, killing at least 21 people.
The monitors were investigating a shooting when the blast happened.
The team are said to have lost their vehicles but were apparently safe with rebels from the Free Syria Army.
Internet footage showed damage to a car of the type used by UN monitors.
Violence has continued in Syria in spite of last month’s ceasefire, threatening efforts to find a political path out of the bloodshed.
The leader of the opposition umbrella group the Syrian National Council has reportedly been re-elected for another three-month term.
But Burhan Ghalioun, who has long been living in exile in France, has been criticised for failing to unify the organisation.
The authorities in Damascus say more than half of eligible voters turned out for last week’s
At least one independent figure is said to have been voted in.
But opposition leaders said credible voting was impossible in areas under siege.