NICOSIA: Dozens of journalists at Qatar's Al-Jazeera broadcaster had their mobile communications intercepted by sophisticated electronic surveillance, one of those targeted said on Monday, following a months-long expert investigation.

Interceptions of 36 journalists' phones were revealed in a report by the Citizen Lab research centre at the University of Toronto on Sunday, after they monitored journalists' devices for suspicious activity.

"The impact is very clear and dangerous," Al-Jazeera Arabic investigative reporter Tamer al-Misshal, who was targeted, told AFP.

Al-Jazeera said it approached Citizen Lab in January after receiving suspicious messages on a device used to contact people for comment.

The experts agreed to monitor the device's internet traffic, subsequently discovering data, which could have included sensitive material, was being sent clandestinely to a hostile server.

"We obtained logs from an iPhone 11 device inside Al-Jazeera networks while it was infected. Our analysis indicates that the (spyware) has a number of capabilities," Citizen Lab said in its report.

These included interception of audio from the microphone - both calls and ambient noise - as well as images from the camera, the report said. "In addition, we believe the implant can track device location, and access passwords and stored credentials," it added.