Rights group Amnesty International has accused Syrian forces of waging "relentless” and “indiscriminate" attacks against its people.

The London-based rights group, which accompanied its report with video footage, said "civilians, many of them children, are the main victims of a campaign of relentless and indiscriminate attacks by the Syrian army".

Amnesty said the findings were based on "first-hand field investigations carried out in the first half of September".

During that period, attacks killed "166 civilians, including 48 children and 20 women, and injured hundreds in 26 towns and villages" in the northwestern regions of Idlib, Jabal al-Zawiya and the northern Hama area.

Donatella Rovera from Amnesty International told Al Jazeera that she witnessed “evidence of indiscriminate air bombardment and artillery strikes” in all of the 26 towns and villages she visited in northern Syria".

 “The use by [Syrian] government forces of what are essentially battlefield weapons cannot be aimed at specific targets but that fall randomly over civilian residential areas is what has made the situation so much worse over the last six or seven weeks,” Rovera told Al Jazeera from neighbouring Turkey.

“The number of civilians that have been killed or injured has increased dramatically,” Rovera said.

Border crossing seized

Meanwhile, Syrian rebels have seized control of a border crossing on the frontier with Turkey and pulled down the Syrian flag.

A reporter from the Associated Press at the scene on Wednesday said Syrians on the Turkish side of the border were celebrating and yelling, “I am a free Syrian!" People are moving freely across the border, crawling under barbed wire.

There were fierce clashes on Tuesday as rebels and regime forces fought for control of the Tal Abyad crossing.

Syria's rebels control several other border crossings into Turkey but it is believed to be the first time they have tried to take the border area in the northern province of Raqqa.

While in Damascus, an opposition activist in the Tadamon neighbourhood told Al Jazeera by phone on Wednesday that rebel fighters had withdrawn from three areas of the capital due to what he said was a "lack of ammunition".

The activist, Abu Qais al-Shami, said the areas, Hajar al-Asswad, al-Qadam and Asseil, were also under a tight Syrian army siege as they were struck by air bombardment and tank shelling.