ISLAMABAD, May 4: Opposition parties voiced loud protests on Tuesday against what they called 'state victimization' at the start of a Senate session called at their request to discuss matters including national security.

Their complaints ranged from an alleged used of state machinery to punish opposition parliamentarians to a temporary ban on the movement of wheat from Punjab to other provinces.

There was no immediate government response to the protests in the absence of interior and food ministers from a one-sided and trouble-free debate allowed by Chairman Mohammedmian Soomro under a prior agreement with the representatives of both sides in the upper house.

But the treasury and opposition benches joined voices to condemn Monday's killing of three Chinese officials in Gwadar, alleged inhuman treatment of Iraqi prisoners held by US forces and the killing of seven Pakistanis by Macedonian police two years ago.

Democratic Alliance and PPP parliamentary leader Raza Rabbani initiated the debate by accusing the government of using "state terrorism" against its political opponents in the aftermath of the passage of the NSC bill.

He particularly protested against registration of cases under the Anti-Terrorism Act against a PPP MNA from Rawalpindi, Zamarrud Khan, who took up the cause of local transporters against an alleged monopoly given to a bus company on several Rawalpindi-Islamabad routes and reported raids on the houses of convicted PML-N acting president Javed Hashmi in Lahore and Multan.

Mr Rabbani said that like Mr Hashmi's conviction, the authorities were seeking to make "an example" of the PPP MNA for joining the protest against alleged monopoly given to the Varan bus company that he said was owned by the daughter of a former army general.

"There is a limit to victimization," he said and vowed that the opposition would never bow before the government pressure. Mr Rabbani's indictment of the government was supported by several other opposition members, including Sardar Mahtab Khan, Prof Khurshid Ahmad and Prof Ghafoor Ahmed and Asfandyar Wali, who raised the issue of Punjab's ban on the movement of wheat.

"Can we promote democracy like this?" Prof Khurshid asked, and said he had also received a message from Mr Hashmi's daughter, MNA Maimoona Hashmi, about a police siege of the family houses in Lahore and Multan.

Prof Ghafoor Ahmad accused the government of victimizing those who spoke the truth and warned it of "serious consequences" if amends were not made. Asfandyar Wali, who was bitter about the ban on wheat movement from Punjab, called for an inquiry into what he called bank loans worth millions of rupees given to hoard wheat stocks and the rejection of imported Australian wheat that was later sold in the United Arab Emirates and Indonesia.

He said if the Punjab government's argument of continuing the wheat ban until it met its procurement target of 3.5 million tons was accepted, then it should not have any grudge if other provinces did the same about their resources like electricity and gas.

Several senators from Balochistan blamed the government policies for the creation of a situation in which three Chinese officials in Gwadar were killed in a car bomb blast.

At the outset of the session, the house unanimously passed a resolution moved by leader of house Wasim Sajjad expressing its "profound grief and shock" at the killing of the Chinese officials.

The resolution called the attack a terrorist act but said it could not undermine the "time-tested" friendship between Pakistan and China. Towards the fag-end of the proceedings, PML-Q Senator Mushahid Hussain Syed protested against the "reprehensible crime" of the murder of seven Pakistanis in Macedonia and the reported maltreatment of Iraqi prisoners by US forces.

The house was adjourned until 5pm on Wednesday when the opposition parties are likely to seek a discussion on the consequences of last month's passage of the NSC bill.