NSW Police are investigating whether a fire at one of Telstra’s mobile sites in the flood-hit town of Mullumbimby that shut down its mobile phone service for several thousand people was deliberately lit by anti-5G activists.

The area is one in which Telstra has seen some of the strongest resistance to new 5G technology in recent years and Telstra regional general manager Mike Maron said the fire appeared to be a “selfish act of vandalism”.