EXCLUSIVE

TMZ has confirmed ... Junior Seau is dead. Cops suspect suicide.

Cops in Oceanside, CA are investigating a possible shooting involving former NFL star Junior Seau ... law enforcement sources tell TMZ.

We spoke with an investigator in the coroner's office .. who told us they got a call to respond to the scene ... though the details surrounding the situation are still unclear.

Cops are currently at a residence where 43-year-old Junior is believed to be staying.

People in law enforcement are telling us Junior Seau is dead ... but we are unable to confirm that right now.

Attempts to reach Seau and Seau's people have been unsuccessful.