The Rio de Janeiro outfit have completed a deal for the Argentine, along with former star Alex, before the Brazilian transfer window closed
The Argentine was key in Newell's Old Boys' Primera Division triumph this year while on loan with the Rosario outfit and has sealed a €5.3 million (£4.5m) move to Brazil.
Alex, meanwhile, spent five years between 2004 and 2009 at the Beira-Rio and returns following spells with Spartak Moscow, Corinthians and the Qatari club on a two-year deal for a €2m (£1.7m) fee.
"Internacional are gaining two big reinforcements for the second half [of the Brasileiro]: striker Scocco and midfielder Alex have agreed to join and will officially be presented in a few days," read the club's official website.
Internacional, currently coached by former Brazil boss Dunga, are currently fifth in the Brasileiro, trailing leaders Botafogo by four points.
Scocco, 28, scored two goals on his Argentina debut, while the 31-year-old Alex has won four Brazil caps.