The news was first reported by FOX8 New Orleans.
Te'o, 28, has been out of the NFL this season after spending the previous two years in New Orleans. The Saints apparently needed more depth after starting middle linebacker Kiko Alonso and starting strongside linebacker A.J. Klein suffered unspecified injuries during last Thursday night's win at Atlanta.
The severity of those injuries is unknown. The Saints' first practice report will come out Wednesday as they prepare for a high-profile home date with the San Francisco 49ers on Sunday. Both teams are 10-2.
The Saints previously lost starting middle linebacker Alex Anzalone to a season-ending shoulder injury in Week 2. But they still have the NFL's third-ranked run defense, allowing just 88.6 rushing yards per game. The 49ers' offense ranks second in the NFL with 148 rushing yards per game.
Te'o, a Heisman Trophy runner-up at Notre Dame, spent his first four seasons with the San Diego Chargers. He has started 46 games in his career, including 12 with the Saints, with 301 career tackles. He has primarily played middle linebacker. He was a healthy inactive for most of last season, appearing in only five games.