UNITED NATIONS — Lebanon is under massive pressure as tens of thousands of refugees fleeing the war in neighboring Syria continue to stream in, likely reaching a total of 1.5 million people by the end of the year and heightening tensions in the tiny, overburdened country, UN officials said Monday.

The number represents one third of Lebanon’s estimated population of 4.5 million, and unlike Turkey and Jordan, Lebanon has no refugee camps for Syrians, who are scattered all over in informal settlements, living with relatives or renting homes.

UN spokesman Stephane Dujarric said that over a million Syrian refugees are registered with UN agencies in Lebanon, and 50,000 new arrivals continue to sign up each month. Those figures don’t include up to one million Syrians who are believed to be living in Lebanon and who have not sought help from the United Nations.

In Geneva earlier, the UN’s humanitarian chief in Lebanon, Ross Mountain, told reporters that at this rate, Lebanon will be home to 1.5 million registered refugees by year’s end.

The high numbers mean huge pressure on public services and the communities that are welcoming the Syrians. In turn, this translates into heightened tensions among both communities, Mountain said.

“Already we are seeing signs of tension, not surprisingly, between the Syrians that are arriving and the Lebanese host communities,” Mountain told reporters. “But the fear that many of us have is that, that mixed with other factors could mean rising tension between communities within Lebanon.”

Most of the fleeing Syrians are moving into Lebanon’s poorest regions, such as the Bekaa Valley and Akkar, he said.

“There are 225 localities that contain 86 per cent of the refugees and 68 per cent of the poorest Lebanese. The problems that they have had before are of course exacerbated by this influx,” Mountain said.

The UN warnings came as the activist group Syrian Observatory for Human Rights reported that the death toll in Syria’s three-year conflict has climbed past 160,000. The United Nations no longer updates its own tally of the Syrian dead, saying it can’t verify the numbers.

Copyright 2014 The Associated Press.