Wires spill out of the vandalised light at Manuka Oval.

Wires spill out of the vandalised light at Manuka Oval. Photo: Jeffrey Chan

Mystery surrounds a vandalism attack on one of the new light towers at Manuka Oval, with police examining if a perimeter fence was bent to gain access, and an inner south residents group saying no local would have been responsible.

ACT Policing began an investigation on Monday after electrical workers installing the light towers found about 30 cables cut by pliers when they arrived at work on Sunday.

While there is no known motive for the attack, ACT Economic Development Directorate capital works director Hamish McNulty said it would be a ''sad situation'' if it had been done in protest.

One of the six field lights went up at Manuka Oval on Thursday, December 13.

One of the six field lights went up at Manuka Oval on Thursday. Photo: Melissa Adams

''I'd be very disappointed if this was the way someone chose to indicate their displeasure about the lights,'' Mr McNulty said.

''We did a lot of consultation and were open to public comment. It'd be a sad situation if it has come to that, and I personally don't think it has.''

The installation of the lights is a decades-long dream for Canberra sport fans, who have waited patiently for the chance to watch AFL and cricket under lights.

Wires were cut at the base of one of the newly-installed light poles at Manuka Oval.

Wires were cut at the base of one of the newly-installed lights over the weekend. Photo: via Twitter / @AffinityET

The delay was partly due to strident opposition in the local community, caused by concerns about light pollution. But that opposition has softened considerably in the last decade and there were only two objections to the development application.

Inner South Canberra Community Council chairman Gary Kent said residents of the area had accepted lights were inevitable. Concerns about the ground had more to do with parking and traffic.

''I have no doubt that the vandalism was not caused by local residents,'' Mr Kent said. ''They just wouldn't do it. The people I know in the community are all very responsible. They've made their concerns known through the right channels.''

The damage is not expected to delay completion of the six towers and will not impact on Ricky Ponting's farewell under lights when he leads the Prime Minister's XI against the West Indies on January 29.

The repairs are expected to cost between $1000 and $10,000. While relatively minor, Brendan Read, director of the electrical company working on the project, said the damage was demoralising.

''It just hurts the workers,'' Mr Read said. ''There's probably just the disappointing part of turning up yesterday and finding that some of the cables have been cut.

''Yesterday we had 11, 12 guys on site, and they're just down.''

Coincidently a group of local residents in inner city Sydney gathered on Monday night to protest the testing of lights at Drummoyne Oval in the inner west.