Hayden Panettiere's Mom Says Drugs Investigator Brought Into Death Probe

Hayden Panettiere's mother says cops are taking a hard look at drug use in the police investigation into her death ... even bringing in a narcotics investigator to help.

Lesley Vogel told NBC News Wednesday that she's been informed cops are investigating the death ... adding she's even been told they brought in a narco detective.

She doesn't know where they're at in the investigation necessarily ... but Lesley adds the authorities seem to have quite a few questions regarding Hayden's death.

We broke the story about the investigation ... police are looking to see if some illegality is behind her death.

As you know ... Lesley's been quite vocal since Hayden passed away Sunday ... putting out a controversial statement about her late daughter.

Lesley noted it was a tragedy Hayden died ... before focusing on how Hollywood corrupted her daughter and led her down a path that ultimately culminated in her death.

Gayle King ripped Lesley for the statement on "CBS Mornings" Wednesday ... claiming it immediately made her think, "Thanks for nothing, Mom."

Hayden was pronounced dead Sunday after her boyfriend Brian Hickerson's brother -- Zach -- found her unresponsive. Despite first responders' best efforts to resuscitate her, she was pronounced dead at 2:32 PM inside a residence in Greenville, South Carolina.

Lesley has openly questioned why the suspected overdose took place Sunday afternoon ... outside of prime partying hours.