An unknown amount of potassium nitrate, which can be used to make explosives, was found in an Astoria, Queens home because a worried landlord asked the FDNY to take a look at some materials after an apartment fire early Tuesday morning, the NYPD said.

The firefighters then contacted the police, who charged Marak Squires, 37, with reckless endangerment after the material was found at his 19th Street apartment following a blaze that broke out shortly before 2 a.m., the NYPD said.

Squires, who appeared distraught, the NYPD said, was taken to a Manhattan hospital to be evaluated.

The Joint Terrorism Task Force, which includes the FBI and the NYPD, plans to search the apartment once they obtain a warrant, and Squires may face additional charges, the NYPD said.

No assembled devices were found, at least not initially, the NYPD said.

Potassium nitrate, also called saltpeter, is used to make fertilizer, matches, glass and explosives.

Lead-contaminated drinking water was found in nearly 3,000 water fixtures in Long Island schools. NewsdayTV's Andrew Ehinger reports.  Credit: Newsday/Drew Singh; Howard Schnapp; Pond 5

'You have neurologic effects, you have hematological or blood effects' Lead-contaminated drinking water was found in nearly 3,000 water fixtures in Long Island schools. NewsdayTV's Andrew Ehinger reports.

Lead-contaminated drinking water was found in nearly 3,000 water fixtures in Long Island schools. NewsdayTV's Andrew Ehinger reports.  Credit: Newsday/Drew Singh; Howard Schnapp; Pond 5

'You have neurologic effects, you have hematological or blood effects' Lead-contaminated drinking water was found in nearly 3,000 water fixtures in Long Island schools. NewsdayTV's Andrew Ehinger reports.

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