A Syrian rights group says security forces have attacked a rebellious town in the country's central province of Hama, killing 34 people including children.

The Britain-based Syrian Observatory for Human Rights says government artillery and gunfire hit the town of Souran on Sunday. There was no independent confirmation of the casualties.

Elsewhere, a roadside bomb exploded near a team of U.N. officials and journalists who were touring the Douma suburb of Damascus. No one was hurt by the blast, which was about 150 meters from a group that included visiting U.N. peacekeeping chief Herve Ladsous and the head of U.N. observers in Syria, Maj. Gen. Robert Mood.

A Syrian security official said gunmen had been active in Douma prior to the explosion, attacking and wounding about 30 security personnel. Recent fighting between government and rebel forces in the district has left its streets largely deserted. Douma has been been a major center of the 14-month uprising against Syrian President Bashar al-Assad's 11-year rule.

Two senior aides of Mr. Assad appeared on state television on Sunday to refute claims that rebels had assassinated them. Rebel claims on the Internet said several senior officials of the Assad regime, including Interior Minister Mohammad al-Shaar and former defense minister Hassan Turkmani, had been killed in a sophisticated attack.

Meanwhile, a deadly shooting also was reported in Lebanon, the latest in a recent series of deadly sectarian clashes triggered by the Syrian conflict.

Lebanese troops opened fire on a speeding car carrying a Sunni cleric and his aide through a military checkpoint in the country's north. Both men were killed. Cleric Ahmed Abdul-Wahid and his aide were members of Lebanon's anti-Assad alliance, which supports the Syrian revolt.

The Lebanese military issued a statement of “deep regret” and said an investigation of the incident has been launched. The cleric's supporters protested his death by burning tires and blocking roads in parts of northern Lebanon.

Fighting between pro- and anti-Assad groups in the northern Lebanese city of Tripoli has killed at least eight people in the past week. Lebanese Alawites, members of the Syrian president's minority Muslim sect, have clashed with Lebanese Sunnis who sympathize with the largely-Sunni led uprising against Mr. Assad.