Isis propaganda video shows two Syrian activists being executed

The video ends with what appears to be a threat to murder another man

Isis has suffered a number of high-profile losses (Getty)

Isis have released a brutal propaganda video in which an interrogator appears to execute a pair of activists who bravely worked against the extremist group in Syria.

Faisal Hussain al-Habib, 21, and 20-year-old Bashir Abduladhim al-Salem, who is identified with the surname al-Saado in some reports, operated in the so-called Islamic State’s de facto capital of Raqqa.

The two men lived in the city, a source from the leading anti-Isis organisation Raqqa is Being Slaughtered Silently (RBSS), which works to expose the group’s regime, told The Daily Beast.

Isis captured al-Salem at his home, while al-Habib was seized as he was preparing to release information on the terrorist group, the men are shown saying in the video while dressed in orange jumpsuits.

In the carefully crafted footage entitled ‘They are the Enemy, Beware of Them’ a masked Isis interrogator accuses the pair of being ‘informants’ and distributing anti-Sharia leaflets in Raqqa.

At one point, the Isis member asks the men how they used smart watch cameras to capture intelligence sites in Raqqa and Deir ez-Zor, Syria, Mail Online reported.

As the interrogator flicks through a stack of documents, the pair claim Hamoud al-Mousa, a neighbour and founding members of RBSS, gave them the camera watch and glasses to copy the files.

Al-Salem continues that al-Mousa paid him $400 for the photographs revealing the activities of the extremist group, and would task him with encrypting the information and sending it to Turkey.

Al-Salem and al-Habib are tragically tied to two trees and executed at the end of the video.

It ends with the threat of further brutality, as a man with a blurred face identifies himself as Mohammed al-Mousa, who the RBSS source told The Daily Beast is the father of Hamoud al-Mousa.

If the video follows the pattern of previous Isis clips, the man's appearance may be a threat to his life.

The clip is the group's latest attempt at spreading fear and recruiting loyal fighters to its ranks. Another video published last week showed a 25 men being killed in the historic town of Palmyra in central Syria as hundreds of people watched.