Updated below. Someone stole brass sprinklers valued at $10,000 from a senior-citizen apartment building construction site in Fridley, according to the Fridley Police Department.

Fridley Police Lt. Mike Monsrud summarized the incident by email Thursday:

Sometime Tuesday night into Wednesday morning person(s) unknown took 143 brass fire sprinkler heads from 6490 Central Ave. This building is under construction and the sprinkler heads were taken from an unlocked container sitting in front of the building. The case is under investigation.

The incident was reported on Wednesday at 8:06 a.m., according to police, at the former Sandee's Restaurant site at Mississippi Street NE and Old Central Avenue NE.

That is where Trident Development is building a 70-unit senior-citizen apartment complex called  "Landmark of Fridley."

There was no suspect information at the time of the report.

The missing sprinkler heads are "Tyco brand (model BB1)," according to ScrapTheftAlert.com, a national clearinghouse website for information about thefts of metal items.

Trident Development was not immediately available for comment Thursday morning.

Editor's note: Thanks to NE Minneapolis Crime Watch & Information for the tip.

Update (8:30 p.m. Thursday): The St. Paul Pioneer Press reported that whoever took the sprinkler heads will likely face a challenge turning a profit from them:

The problem the thief or thieves face now is where to unload them, Monsrud said.

Police have alerted all local scrap metal sites to be on the lookout for someone with the stash.

"They're going to have a hard time getting rid of them," Monsrud said.

The Pioneer Press also clarified exactly how the items were stored when they went missing: "sitting in a box inside an unlocked container," the article said, citing Monsrud.