Warning that no force could prevent Pakistan from disintegrating if military rulers remained in power, an opposition alliance and Baloch parties have threatened to launch a joint civil disobedience movement against the army's continuation in government.

Leaders of the opposition Alliance for Restoration of Democracy, Pakistan's Oppressed Nationalist Movement (PONM) and Baloch nationalist parties gave the threat at a protest rally in Baloch capital Quetta on Monday.

Thousands gathered at a football stadium in the city on Monday evening to take part in the second rally called by the local and national opposition parties to protest against the killing of Baloch leader Nawab Akbar Bugti in a military raid on August 26.

A resolution paying tribute to Nawab Bugti demanded exhumation of his body by an international medical board under the supervision of Pakistan's Human Rights Commission to ascertain the cause of death.

Throughout the meeting, group of youths continuously raised slogans against the state and demanded resignations from the assemblies, Dawn reported.

"The opposition leaders said no power could stop the disintegration of Pakistan if military rulers remained in power," The Nation reported on Tuesday.

Speakers at the opposition rally stressed the need for all opposition parties to form a grand alliance to launch a decisive political movement against the Musharraf regime to rid the nation of military dictatorship, which they said, was the root cause of disharmony between Punjab and the smaller provinces.

He maintained that without giving equal rights to the Balochs, Pukhtuns, Sindhis and Seraikis, no one could ensure a stable Pakistan.

"We want every province to be granted complete autonomy. Balochis should be the owners of their own resources and the same should be applied to the other provinces," he said.

Raja Zafarul Haq of the Pakistan Muslim League-Nawaz said Punjabis sympathise with the Baloch people, but "there is a section of vested interests in the province that are widening the gap between Punjab and other provinces".

Sardar Akhtar Mengal, president of the Balochistan National Party, said the Balochis demand rights equal like other Pakistanis.

"We refuse to live in a Pakistan where we are treated like slaves".

In his address Senator Isfandyar Wali, President of the Awami National Party and grandson of Frontier Gandhi, said the government appeared unlikely to end its use of force against its own people, despite this policy bringing Pakistan to "the worst phase of its history".

Shah Mahmood Qurashi of the Pakistan Peoples' Party said there were two classes in the country - the oppressor and the oppressed. "Democratic forces must unite to fight the military until it decides to return to the barracks".

Cricketer-turned-politician Imran Khan, who heads the Tehrik-e-Insaaf party, said lack of democracy was the root cause of unrest in the smaller provinces and urged all parties to launch a civil disobedience movement.