Not too sure how much was taken, five people have been caught in regards to this theft:

Copper thefts cause transport chaos
November 22, 2006 04:46pm
Article from: AAP

COPPER thieves are causing major disruptions to Melbourne's rail network, stealing overhead wires as world copper prices soar.

Thefts of wires have caused delays to more than 500 trains in the past three months, and today shut down two train lines in the morning peak, stranding thousands of commuters.

Police set up a taskforce 10 days ago to tackle the growing problem and earlier this week they arrested five people.

A 36-year-old Narre Warren man was remanded in custody today after appearing at the Melbourne Magistrates Court charged with theft and criminal damage.

Four others will be summonsed to appear in court at a later date.

Detective Senior Sergeant Brian Clarke, of the Transit Crime Investigation Unit, said a number of groups appeared to be responsible for the thefts and the entire network was being targeted.

He said detectives were working with intelligence and forensic services to track down opportunistic thieves, who were risking their lives for the metal.

He also said the gain did not appear to be worth the risk, as the wire would only fetch hundreds of dollars on the scrap metal market, despite the high world price.

"What they are doing is life-threatening and it's only a matter of time before someone is killed or injured," he said.

Det Sen Sgt Clarke said police were working closely with the Scrap Metal Dealers Association to track down the thieves.

Connex Trains spokeswoman, Kate De Clercq, said rail networks around the world were being targeted by copper thieves.

"We have had more than 20 incidents since the start of September, resulting in more than 500 trains being delayed across the network," she said.

Ms De Clercq said trains were stopped on the Epping and Hurstbridge lines for about 90 minutes in today's morning peak after it was discovered copper wire had been stolen in West Richmond.

She said power was turned off on both lines between 7.40am (AEDT) and 9.06am while the overhead line was fixed, forcing thousands of passengers onto buses and trams into the city.
http://www.news.com.au/heraldsun/story/0,21985,20802479-5005961,00.html