Deceased firefighter Daniel Sweeney's family filed court papers Friday putting the owners of the abandoned warehouse where Sweeney died on notice that they intend to sue.

Sweeney, 25, died along with Lt. Robert P. Neary, 60, in the five-alarm fire that broke out in an abandoned warehouse in Kensington last month.

Attorney Joel Rosen, who is also representing firefighters Pat Nalley and Francis Cheney, who were injured in the blaze, filed a legal document in Common Pleas Court putting the owners on notice that he intends to sue, although no complaint has yet been filed. The document also includes accompanying requests for financial data and other records of the defendants, who include York Street Property Development L.P., York Street Property Development LLC, YML Realty Inc. and Yechiel Lichtenstein and Nahman Lichtenstein.

Rosen has previously represented firefighters and other first-responders injured in the line of duty.

Sweeney and Neary were killed when a wall collapsed in an adjoining furniture store.

An investigation into the cause of the fire is pending. A grand jury is also investigating the fire to determine if criminal charges are warranted.

Contact Michael Hinkelman at 215-854-2656 or hinkelm@phillynews.com or follow on Twitter @MHinkelman.