Police and fire authorities are expanding their investigation into a recent string of fire sprinkler thefts across southeast Louisiana.

Thefts of the brass sprinklers are on the rise, as the devices can be sold at recycling centers for several hundred dollars apiece, the state Fire Marshal’s Office said at a news conference Thursday.

“In times that buildings are burning, people are trying to escape and firefighters are in harm’s way, these sprinklers would not have performed properly,” Fire Marshal Butch Browning said.

He said the investigation began earlier this month after Kenner Fire Prevention Bureau officials notified his office about devices stolen from a theater, a department store and Ochsner Medical Center.

Brothers John M. Flattmann, 36, and Jason M. Flattmann, 31, both of Ponchatoula, were caught on separate surveillance footage prying sprinklers off the side of a Metairie condominium building and later selling the devices at scrap yards in Tangipahoa and Jefferson parishes, according to the Fire Marshal’s Office.

The men were arrested last week on unrelated theft charges and await additional charges tied to the sprinkler thefts.

More than a dozen businesses in Hammond also were targeted, Browning said. Authorities are canvassing buildings in the area and have identified at least 26 missing sprinklers so far.

Browning said it’s not clear if the Flattmanns are suspected in all those thefts.

Browning asked anyone with information on sprinkler thefts to contact the police or his office.