United Nations relief agencies said on Friday (July 21) they needed urgent access to southern Lebanon to get medical aid and food to tens of thousands of people driven from their homes by Israeli bombing. They warned that disease could sweep through overflowing refugee centres and overwhelmed hospitals unless Israel guaranteed the security of trucks ready to take in water purification and sanitation supplies. Aid agencies said security and access were the big issues halting them from getting to millions of helpless people in Lebanon.Although main roads had been largely destroyed by Israeli action, U.N. trucks could take secondary routes if they had clearance. Christian Humanitarian Association for Aids, Caritas, opened the gateway for humanitarian aid, distributing food to displaced refugees and treating the wounded. Their services offered a brief respite from the constant bombardment of Israeli missiles. "Shelling, destruction something we never witnessed before. We have been through a lot of big wars but we did not witness such destruction like this ever. The kids are very afraid in a very miserable situation. We personally are not afraid and we can handle the situation but waht's the guilt of these children and what can we say to them can we say to them you have to bare war, they don't understand what's war. A child says he wants to eat, Israel has no pity. We call on all humanitarian and relief associations such as Caritas or any politician that still have mercy to care about these children, the history will talk about him. The children are innocent and people can't breathe anymore they tell us to leave the area and go to north for whom will we leave the area?" asked one refugee. UNICEF children's agency spokeswoman Wilvina Belmonte said: "Children are bearing the brunt of the hostilities and we have to be allowed to help them get through this crisis." She said one third of the Lebanese dead so far were children, and they accounted for nearly half of those displaced, especially from the mountain regions where Hizbollah has a strong presence and which have been especially hard hit. Israel said late on Thursday (July 2) that it had been in contact with U.N. agencies and relevant non-government organisations (NGOs) to try to facilitate the flow of humanitarian aid to Lebanon, on which it has imposed a blockade. The Swiss-based International Committee of the Red Cross (ICRC) said it had sent two trucks early on Friday with 24 tonnes of food, first-aid kits and medicine from Beirut to the southern port of Tyre, where the main hospital is overwhelmed. But agencies said roads -- including routes along which supplies could flow from U.N. supply bases in Syria and Jordan -- were still being bombed as Israel pressed its drive to force Hizbollah forces out of the south of Lebanon. Over 300 people have died in the country and an estimated half a million people have fled their homes over the past 10 days since Israel began the bombing following the abduction by Hizbollah of two its soldiers in a cross-border raid. Matthias Burchard of the UNRWA relief agency for Palestinians in the region said Israelis planes were targeting roads from Syria -- where UNRWA had opened its humanitarian supply stores to send aid to Lebanon. To find out more about Reuters visit www.about.reuters.com .