DETROIT >> The electrocution of a 12-year-old Detroit girl has exposed a new risk in a city that’s turning the corner nearly two years after emerging from bankruptcy: miles of obsolete power lines that could fall from poles and turn deadly.

K’Brianna Griffin was killed in September when she came in contact with a downed line in a friend’s yard. The line was inactive, but it was energized and dangerous because it was resting on a live DTE Energy power line that was carrying electricity.

An investigation turned up details that made the tragedy even worse. DTE, the local utility, said one of its workers saw the downed line in July, weeks before K’Brianna’s death, taped off the area, warned neighbors and notified the city, which owned the line. The city, however, never removed it.

Now state utility regulators are urging action to prevent more peril. In a report last week, staff at the Michigan Public Service Commission said it is Detroit’s responsibility to remove abandoned wires that once powered neighborhood street lights in a 138-square-mile city that’s larger than Boston and Minneapolis combined.

Detroit told the agency that it could cost $35.7 million and take years to remove 900 miles of overhead wire. DTE, which controls the poles, puts the price tag at more than double if other maintenance work is included.

“Only the future removal of the arc wire will entirely eliminate the safety threat. … Without a city of Detroit formal commitment, the possibility exists that the status quo could return,” Public Service Commission staff said.

It’s another challenge for a city trying to refresh itself, nearly two years after emerging from the largest municipal bankruptcy in U.S. history. It is spending millions of federal dollars to demolish vacant houses — more than 10,000 so far — that can be havens for crime while eating away at neighborhood property values and sapping optimism.

Below ground, aging water pipes and infrastructure are vulnerable to ruptures. Street lights have been revived by a new independent agency that focuses solely on that task. About three years ago, 40 percent of lights weren’t working due to copper theft, old technology, dead bulbs and a lack of money. The new lights don’t use the old power lines.

The city’s chief attorney, Butch Hollowell, declined to address questions from The Associated Press about whether Detroit will follow recommendations about removing all wires. He said city workers have been told that no downed lines will be left unattended until the wire is cut and any immediate danger is eliminated.

“The city cannot comment further on this tragic matter considering it remains under review” by state regulators, Hollowell said, referring to K’Brianna’s death.

Separately, he told the Public Service Commission that Detroit “is in fundamental disagreement” with DTE Energy’s report about the electrocution. He didn’t elaborate.

The commission has no authority over Detroit. But it does oversee DTE, whose poles hold the abandoned wires. Commission staff said the utility should work with the city on a long-term plan if Detroit doesn’t act on its own.

K’Brianna, known as “KB” to friends, enjoyed dancing, drawing and dogs. Tamika Robinson said her daughter was making a video in a friend’s yard when she backed into the power line.

“Her eyes got really big and she just dropped. The wire got caught on her jacket,” Robinson said. “Her goal was to be a veterinarian. She was as unique as her name.”