I would also severly doubt the brutes because if you read the novels the brutes dont show up until after the first halo when master cheif gos on his sabotoge mission. "halo first strike". And since the game is set befor the first halo I would say no.
Death is only a new begining! So fight hard, Fight fast. Dont let your feet touch the ground for fear of stoping. Become who you were born to be become a spartan!