The secretary-general of the Syrian Arab Red Crescent was shot dead on Wednesday as he travelled outside the capital Damascus in a clearly marked vehicle, the International Committee of the Red Cross (ICRC) said.

Doctor Abd-al-Razzaq Jbeiro, also head of the Red Crescent branch in the northern town of Idlib, was on the highway to Idlib from Damascus after attending meetings at Red Crescent headquarters, the agency said in a statement.

Regardless of the circumstances, the ICRC condemns this very severely, Beatrice Megevand-Roggo, head of ICRC operations for the Near and Middle East, told Reuters in Geneva.

She added that the lack of respect for medical services remained a major issue in Syria.

Syrian state television blamed terrorists for the killing, saying he had been assassinated in Khan Sheikhoun district.

The president of the Syrian Arab Red Crescent, Dr. AbdulRahman al-Attar, said that he has officially requested the Syrian authorities to launch an investigation into the death of Dr. Jbeiro, the ICRC said in a statement.

Jbeiro, born in 1945, had also previously worked as director of Idlib hospital.

The ICRC is the only international agency deploying aid workers in Syria. A local Red Crescent volunteer was killed and three others were injured in the flashpoint city of Homs last September when an ambulance came under heavy fire.

More than 5,000 people have been killed in a 10-month-old uprising against the rule of President Bashar al-Assad, the United Nations said last month.

REPEATED INCIDENTS

Megevand-Roggo, who had just returned from a two-week trip to Syria, Yemen and Lebanon, said checkpoints and harassment in Syria prevented ambulances and medical workers from evacuating and treating the wounded, some of whom have died as a result.

It is very difficult for the wounded, notably those among the opposition forces, to get access to necessary medical care. It is difficult for medical personnel to do their work without being under pressure, she said. Lives have been lost.

There have been repeated incidents where Red Crescent ambulances have been shot at, our volunteers have been wounded. Their work is very dangerous, she said.

Gulf Arab monitors headed out of Syria on Wednesday after their governments said they were certain the bloodshed and killing of innocents would continue and the Arab League pursued U.N. support for a plan to end Assad's rule.

Protests started out as non-violent but today the situation is one of widespread violence in the country because many arms are circulating and many people use them, Megevand-Roggo said.

Our access remains fairly random, we cannot go places with any regularity or frequency, some areas are more problematic than others, she said. We'd like to develop a more regular and frequent presence in affected areas, including rural zones.

The ICRC started visiting prisoners in Syria for the first time last September, including the central prison in Damascus.

But it has been unable to carry out further visits to detention centres due to a disagreement with Syrian authorities over the ICRC's standard terms, she said.

The dialogue is difficult, we are in a situation of stagnation regarding the possibility for us to resume our activities and visit other detention centres, she said.

ICRC terms worldwide include the right to interview prisoners privately about their treatment and conditions of detention and to make follow-up visits.

Syrian authorities say that more than 5,000 detainees were released under Bashar's latest amnesty this month, although activists say this still leaves many thousands more behind bars.

There are certainly several thousand detainees. We have very little information on the situation, Megevand-Roggo said. The most urgent thing is to be able to tell families where their loved ones are being held and to facilitate contact between them.

(Reporting by Stephanie Nebehay; additional reporting by Alistair Lyon in Beirut Editing by Maria Golovnina)