At least 45,000 people have fled intensified fighting in Syria’s southern province near border with Jordan, UN says.

Air strikes on rebel-held parts of southern Syria have put at least three hospitals and medical centres out of service as the Syrian army presses an offensive to retake the area, sources told Al Jazeera.

Lawrence Adam, a Syrian journalist with the pro-opposition Nabaa media group in the suburbs of Deraa, said bombing raids had either completely destroyed medical centres or put them out of services in the opposition-controlled towns of Saida, Al-Harak, Al-Mseifra and Al-Jiza in Daraa province.

“The Al-Mseifra hospital has been completely damaged while hospitals in Saida, al-Harak and al-Jiza were put out of service after midnight, because of air strikes near the facilities,” said Adam.

“The hospital in Al-Jiza was damaged after the regime targeted the town with three air strikes this morning. That’s where a large number of civilians remain,” added Adam.

He had no immediate information on the fate of medical staff or the patients inside the facilities.

Troops loyal to Damascus began ramping up air raids, rocket fire and the use of barrel bombs on rebel territory in Deraa and neighbouring Quneitra province on June 19.

Since then, dozens of people have been killed and more than 100 others have been wounded, according to Adam.

State news agency SANA has said air strikes on Deraa were a prelude to an “advance into the southeastern quarter of the city”.

At least 45,000 people have fled intensified fighting in the southern Deraa province towards Jordan, the United Nations said on Tuesday.

United Nations has warned that escalation in Syria’s south could have dangerous repercussions for the estimated 750,000 civilians in the area [Anadolu]

Call for help

Issuing an urgent call for action, Adam said civilians were fleeing their homes in unprecedented numbers, and have nowhere to go.

“The situation is critical. They (air raids) are targeting civilians from every corner. Families are stranded along the roads with no means to transport them,” said Adam.

“The Jordanian borders are closed and the western suburbs are also under attack,” Adam told Al Jazeera. “We have nowhere to go.”

In response to the movement of fleeing civilians towards the Jordanian border, Jordan’s Minister of State Affairs Jumana Ghanimat said on Sunday the country would be unable to host a new wave of Syrian refugees.

According to the UN’s refugee agency, UNHCR, Jordan has the second-highest share of refugees compared with its population in the world – 89 per 1,000 inhabitants.

Jihad Hamza, a pro-opposition activist in Deraa, called on the international community to act quickly.

“We are terrified. Thousands of families are caught in villages being targeted by the government,” said Hamza.

“There aren’t enough tents or homes to take in the ones moving towards the borders any more.

“Without immediate action from the international community and organisations, we are facing a seriously dangerous situation,” added Hamza.

‘De-escalation’ deal undermined

The government’s offensive is in breach of a “de-escalation” agreement negotiated by the US, Russia and Jordan in July 2017. Since then, the deal largely contained fighting in the southwest of Syria.

Assad said earlier this month that he was still pursuing a political solution for Syria’s rebel-held southwest, but would use military force if the effort failed.

On Thursday, the United Nations warned that escalation in Syria’s south could have dangerous repercussions for the estimated 750,000 civilians in the area.

Syria’s war has killed hundreds of thousands of people and displaced millions since it started in 2011 with the brutal repression of anti-government protests.