A roadside blast wounded six Syrian soldiers as they escorted United Nations monitors
toward the restive southern town of Dara'a.
The explosion hit a military vehicle accompanying the U.N. convoy, blasting out its windows and injuring those inside. The head of the U.N. monitoring mission, General Robert Mood, was in the group headed toward Dara'a, but neither he nor any of the observers was hurt.
He is quoted by his spokesman as saying it was "an example of what the Syrian people were suffering on a daily basis" and that "all forms of violence must stop."
An Associated Press reporter traveling behind the convoy said the blast set off a thick plume of black smoke.
The U.N. vehicles are reported to have passed by the blast site only seconds before.
No one has claimed responsibility for the attack, which comes one day after the International Committee of the Red Cross noted the armed wing of the opposition has turned increasingly to guerrilla tactics. The rebel Free Syrian Army, which has relied largely on machine guns and rocket-propelled grenades, has been out-gunned by the heavy weaponry of the Syrian military.
A statement from the office of U.N. Secretary-General Ban Ki-moon said the blast, and other violence throughout Syria, "call into question the commitment of the parties to the cessation of violence."
U.S. State Department spokeswoman Victoria Nuland called the bombing "another example of why we have got to continue to put the pressure on the Assad regime."
The U.N. observer mission is in Syria to monitor a cease-fire agreed to by both sides last month. Hundreds of people have been killed in fighting, hoever, since the truce went into effect. The U.N. has acknowledged the challenge of the mission, which now comprises several dozen monitors plus civilian advisers. The U.N. plans to boost the team to 300 by the end of the month.
The violence of the past 14 months has wearied many Syrians who have not taken sides in the conflict. The aim of the U.N. plan is to create an atmosphere that is calm enough to allow political talks to get underway, something Damascus University student Rawan Tahmoush hopes will happen soon.
She said all parties should make concessions for the country's sake. In the end, she added, the country is "ours, whether we are for the government or against."