SIS Live has warned its staff to be on their guard for further attacks after the company’s outside broadcast trucks were attacked by rioters.

In an email to staff, SIS Live operations director Nic Christodoulou said that two of the company’s SNG trucks had been been damaged.

The vehicles were in London and Manchester and were targeted by rioters who smashed their windscreens, causing what a spokeswoman described as “cosmetic damage”.

“We have started discussions with our customers on forthcoming events and their risk of any attack,” added Christodoulou.

“In particular we are focussing on events where the units may be visible to the public or parked on public roads. I absolutely urge all staff that due to the unpredictability of these terrible outbursts to remain vigilant and to ensure they do not place themselves or equipment at unnecessary risk.”

The BBC’s news controller, Kevin Bakhurst, described the riots in London as “one of the most difficult stories we have had to cover”.