"We have unearthed a lot. We have in fact netted all the people directly involved in the action but we are trying to see who was behind them, the real links, as they say," Musharraf told reporters at the World Economic Forum in Switzerland on Thursday.
"We think that yes, there is a definite possibility of some al-Qaida in the rear," either ordering or executing the attacks, he added. "We are now trying to see the linkage with our (Pakistani) extremist organisations, we need to establish that still."
Since he came to power Musharraf has survived four assassination attempts on his life. All have been blamed on Islamists.
Two of the attempts occurred in Karachi and the other two in the military capital, Rawalpindi.
His major enemy, al-Qaida, has threatened to assassinate him on a number of occasions and asked the Pakistani tribes to do the same.