State police are investigating a suspicious death at a motel owned by the former FBI informant whose limo company is behind the deadly crash that killed 20 people upstate, according to a report Thursday.

The death at the Crest Inn Suites & Cottages in Ganseveoort doesn’t appear tied to Saturday’s wreck in Schoharie, a state police spokeswoman told the Albany Times Union.

The death at the motel, about 45 miles north of Albany, was reported on Wednesday, and it was ruled suspicious following a preliminary investigation.

The name of the deceased person hasn’t been released.

Both the motel and Prestige Limousine are owned by Shahed Hussain, 62, who helped the feds run a pair of anti-terror sting operations following the Sept. 11 attacks.

One sting involved a purported plot to blow up a pair of synagogues in the Riverdale section of The Bronx.

On Wednesday, Hussain’s son, Nauman Hussain — who’s been running Prestige while his dad is in Pakistan — was charged with criminally negligent homicide in the crash of a customized 2001 Ford Excursion SUV outside the Apple Barrel Country Store & Cafe.

Nauman, 28, is accused of putting improperly licensed driver Scott Lisinicchia behind the wheel of the rundown limo, which the state police said was “unserviceable” following an inspection it failed last month.