Police at the scene and prosecutors would not comment on the actions while Sports Illustrated, citing an unidentified source, reported that Hernandez was not believed to be a suspect in what was being treated as a possible homicide. Police had spoken with Hernandez, the magazine said.
Sports Illustrated reported that the link between Hernandez and the case was a rented Chevrolet Suburban with Rhode Island plates that police had been searching for. The Sun Chronicle of Attleboro, Mass., said the SUV was registered to Enterprise and investigators wanted to analyze it for fingerprints.
The Associated Press could not independently confirm the reports.
No cause of death had been released for the body found about 5:30 p.m. Monday.
Hernandez is represented by the Athletes First agency, which said it has no comment "on the Aaron Hernandez situation." The player's mother said by telephone from Connecticut on Tuesday she had no knowledge of a case involving him.
The Patriots drafted Hernandez out of Florida in 2010. Since then, he has combined with Rob Gronkowski to form one of the top tight end duos in the NFL.
On Tuesday night, some police officers stood on the front steps of Hernandez's home and others could be seen inside. Some walked around the driveway and in the garage with flashlights. Before wrapping up their work for the night, one officer took a box out of the massive house.
"I am aware of the reports, but I do not anticipate that we will be commenting publicly during an ongoing police investigation," Patriots spokesman Stacey James said.
North Attleborough is south of Boston on the Rhode Island state line, not far from the Patriots' stadium in Foxboro.
In 38 games, the 6-foot-1, 245-pound Hernandez has 175 receptions for 1,956 yards and 18 touchdowns. He missed 10 games last season with an ankle injury and had shoulder surgery in April, but is expected to be ready for training camp. The Patriots have not said which shoulder was operated on.
Last summer, the Patriots gave Hernandez a five-year contract. It was worth $40 million, according to reports, and came just months after the team locked up Gronkowski, through 2019.
"Aaron's improved a lot," Patriots coach Bill Belichick said at the time. "He's worked hard, he's improved a lot in all phases of the game - the passing game, the running game, protection and his overall versatility. He's doing a good job for us."
Hernandez played in college with Tim Tebow, who was recently signed by the Patriots.