NI Water has withdrawn workers from an area of Belfast after they were approached by a gang of masked men who smashed their lorry with iron bars and set it alight on Friday.
The contractors were carrying out work as part of a £10m upgrade of water mains across north and west Belfast.
The gang approached them in Ladbrook Drive and smashed the lorry, its windscreen and set it on fire.
The PSNI and Fire Brigade attended the scene and it is not believed anyone was injured during the incident.
A spokesperson for NI Water said the company had to withdraw the workers on the basis of the risk to health and safety.
“Our paramount concern is the safety of our workers and we will not put them in danger. The contractor was working on a £10 million scheme to improve the supply of water in the area, this attack is completely unwarranted, unprovoked and unnecessary. Our teams are there working for the good of the community to provide a safe and reliable service.
“The real shame of this situation is that it will be the local community who will suffer because of the mindless destruction of a few.
“The water mains rehab work which is presently being undertaken by NI Water is solely concerned with the improvement of the quality of water being delivered to our customers and the reduction of interruptions and leakage on the system.
“I would urgently appeal to the local community and their representatives to unite with us in ensuring the safety of our staff and their equipment.”