WARNING: "The following footage contains scenes of brutal and graphic nature."

At least 220 people, mostly civilians, have been killed in yet another massacre in the volatile Hama province of Syria. The death toll is expected to rise substantially as many are still believed to be unaccounted for. Large numbers are reported to be trapped under the debris of burnt and destroyed houses. The unverified footage posted on a social media web site is so graphic we can only bring you a few seconds to watch.

According to activists Helicopter gunships and tanks pounded Tremseh followed by an assault involving the use of heavy weapons It was reported Execution-style killings were carried out by soldiers said. Most of them were slaughtered by knife, including women and children.

This is the single bloodiest incident in Syria since the year long uprising, if the reports are confirmed. The bloodshed comes at a time when UN Security Council members are pushing for more sanctions on the regime, but this is being opposed by Syria's key ally Russia.

Written and Presented by Ann Salter