IDOMENI, Greece — After a brief respite aboard a Greek passenger ship, Syrian refugee Mohamed has found himself stranded on a filthy, chaotic strip at the Macedonian border, his way to the relative security of northern Europe blocked by razor wire and riot police. The 20-year-old geology student, like thousands of others stuck at the Greek frontier village of Idomeni, has made an arduous and often dangerous journey to escape the horrors of the Syrian civil war. What he has found at Idomeni has brought him close to despair and now he simply wants to go anywhere in Europe that is safe. “We just want to survive,” he told Reuters. After making his way through Turkey, Mohamed took a small boat over the narrow stretch of water to Kos, a Greek island where conditions have been dire as thousands of migrants arrive this summer from as far as Pakistan, Iran and Afghanistan. Mohamed, who did not give his family name, covered the next stretch in the relative comfort of the ship which crossed the Aegean to Piraeus. After that came an overland journey to the northern Greek city of Thessaloniki, and from there he walked — 70 km (45 miles) in the burning mid-summer heat. The sight at Idomeni is pitiful. Several thousand refugees and migrants shouted “Help us!” to Macedonian riot police behind the wire. This blocks a railway line that others had used to walk across the frontier as they headed north towards Hungary and Europe's open-border Schengen zone. 'I NEED MY SON' One Afghan couple were separated from their two children in the chaos. “I lost my children last night at about 6 p.m. when the crowd was pushing,” said Mohammed Yasin. “My son is six years old and my daughter is one and a half,” he told a reporter at the razor wire. Minutes after he spoke, a man approached from the Macedonian side carrying a small child, Yasin's daughter. His wife cried as she was handed the girl but the man repeated: “I need my son.” Overwhelmed Macedonian authorities are allowing only small groups over to the town of Gevgelija, laying on trains to take them north. In the meantime, sanitation is dire on the Greek side. The weather turned cold and wet overnight, with fields next to the railway track where migrants have pitched tents becoming muddy. In the morning hours, people huddled around open fires while yet more arrived on foot. Many were trying to find other entry points into Macedonia. Ahmed, 32, stranded with his wife Rane and seven-month-old child, have waited four days at the border, hoping they can head to Germany where they have friends. “It's miserable here. Our child is coughing and we don't have any clothes,” he said. Frustration spilled over into anger, not necessarily directed at the police blocking their way. Meanwhile, shelling and aerial raids by Syrian government forces killed at least 20 civilians on Saturday in Douma, a rebel-held town east of Damascus, a monitoring group said. “At least 20 civilians were killed in the heavy shelling and air attacks since this morning on Douma,” said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights. He said about 200 others were either wounded or still trapped under the rubble. On Sunday, regime attacks on the same town killed more than 100 people. — Agencies