Police Lt. Karen Laser confirmed the death Wednesday but released no other details.
Police responded to a report of a shooting at 10 a.m. at Seau's home on the coast north of San Diego.
Seau was a standout linebacker with the University of Southern California before going to the San Diego Chargers, whom he led to the Super Bowl following the 1994 season.
He remained with the Chargers until 2003 and went on to play with the Miami Dolphins and New England Patriots before retiring after the 2009 season.
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