Israel’s military offensive in Lebanon has forced more than a million people from their homes, including hundreds of thousands of Syrians, who fled conflict in their own country after 2014.

The Syrians were already among the most vulnerable communities in Lebanon, and have faced a long history of hostility and discrimination.

Reports say more than 250,000 Syrians have left Lebanon and returned to Syria, fleeing intensifying Israeli airstrikes.

But for many of the more than 1.5 million Syrian refugees in Lebanon – who have fled years of political persecution or compulsory military service – returning home is a dangerous prospect, human rights groups warn.

Ninety per cent of Syrian refugees live in extreme poverty and were dependent on aid even before the current conflict began, according to the UNHCR.

For years, they have faced xenophobia and violence sparked by local political and religious leaders calling for their expulsion.

Also, strict laws on residency and work permits make it hard to find formal employment, which deepens vulnerability, the UNHCR says.

The humanitarian crisis triggered by Israel’s assault is putting a huge extra strain on a country that was already struggling with protracted economic and political crises, which has seen the rate of poverty triple over the past decade.

Reports say that during Israeli airstrikes, some Syrian refugees have been barred from accessing communal bomb shelters.

Many of these municipal shelters are effectively Lebanese-only, reports say.

And some landlords have taken advantage of the crisis to hike rents. In the northern city of Tripoli, where house rentals would typically be $US300-$US400 a month, landlords are now demanding $US1,000 – profiting from the surge of displaced people looking for accommodation, the reports say.   

UNHCR chief Filippo Grandi said the arrival of refugees in Syria had added another layer of complexity to an already strained humanitarian situation.

The Syrian civil war which began in 2011 has resulted in one of the world’s largest humanitarian crises.

“Families I spoke with had run for their lives and have no idea what tomorrow may bring after an exhausting, dangerous journey to the border. They arrive with few means and in need of urgent relief,” Mr Grandi said, after a visit to the Syrian border.

He said only a quarter of this year’s humanitarian needs in Syria have been funded, while needs are at their highest since the start of the conflict: 13 million Syrians face acute food insecurity and over 650,000 children show signs of stunting from severe malnutrition.

With the main road between Lebanese and Syrian border posts destroyed by an airstrike, refugees are forced to make the journey on foot, with their children and whatever belongings they can carry.

UNHCR – in collaboration with the Syrian Red Crescent, other UN agencies, including the World Food Program and other NGOs – are providing assistance at the border, including water, food items, and blankets. Teams are also supporting the new arrivals with legal assistance, documentation and advising them on administrative and other procedures.

Meanwhile, the NGO Human Rights Watch said it has evidence of numerous cases of returning refugees being “arbitrarily detained, kidnapped, tortured, and killed” by Syrian security agencies.

In many cases families have been separated with women and children returning to Syria, while the men have stayed behind in Lebanon.

Also, among the exodus of people trying to flee Lebanon are migrant domestic workers from countries including Kenya, the Philippines, and Ethiopia, many of whom feel trapped and unable to get to safety.