Hundreds of Pakistanis, joined by dozens of American activists, have launched a motorcade "march" against U.S. drone strikes that they hope will reach the militant-riddled Afghan border region.

The main faction of the Pakistani Taliban has denounced the protest, and it is unclear how far the protesters will get.

The two-day march — in reality a long vehicle convoy — is being led by Imran Khan, the former cricket star-turned-politician.

It began Saturday morning in Islamabad and is intended to end in South Waziristan tribal region, a frequent target of drone-fired American missiles.

The American activists are from the U.S.-based anti-war group CODEPINK.

Drone strike opponents allege such attacks kill numerous innocent civilians and terrorize communities. U.S. officials have said the majority of those killed in the strikes are militants.