HALIFAX, Nova Scotia -- Sen. John McCain says he has no doubt that "political correctness" played a role in preventing concerns about the alleged Fort Hood gunman from reaching the right people.

The Arizona senator said it remains to be determined how big a role it may have had in causing military authorities to ignore warning signals about the shooting suspect.

Army Maj. Nidal Malik Hasan is accused of killing 13 and wounding more than 30 on Nov. 5 at the Army post in Texas.

Colleagues reportedly viewed Hasan, an Army psychiatrist, as belligerent and argumentative in frequent discussions of his Muslim faith.

Investigators are looking into whether the Army missed red flags about Hasan's behavior.

McCain spoke to the AP on Saturday while he was in Nova Scotia attending the Halifax International Security Forum.