BAGHDAD, Iraq - At least a dozen bodies were found buried at a garbage dump on the outskirts of Baghdad today, some of them blindfolded and shot in the head, Iraqi officials said.

In Saddam Hussein's hometown of Tikrit, insurgents launched another attack on Iraq's embattled security forces, using a suicide car bomb to destroy a police minibus, killing eight of the officers on board.

The attack was part of a surge of violence that has killed at least 255 people - many of them Iraqi soldiers and police - since Prime Minister Ibrahim al-Jaafari announced his new government April 28 with seven Cabinet positions still undecided.

Iraq's new Cabinet held its first meeting Thursday to decide a plan of action. Al-Jaafari aide Laith Kuba said the seven vacancies, including the key oil and defense ministries, would be filled by Saturday and parliament would be asked to vote on them Sunday.

Scavengers sifting through garbage for scrap metal and other items to sell stumbled across the bodies at the dump in Kasra Waatash, on the northeastern edge of Baghdad, police and soldiers said.

At Baghdad's central morgue, an official said 12 bodies had been received. Families identified some of the victims as farmers who disappeared recently on their way to a market to sell their produce, said Rahoumi Jassim, a morgue official.

In the Tikrit attack, a silver Opel packed with explosives - and with a taxi sign on its roof - destroyed a police minibus, said U.S. Army 1st Sgt. Brian Thomas and Iraqi army Maj. Salman Abdul Wahid.

The attack at the checkpoint on the eastern outskirts of Tikrit, 80 miles north of Baghdad, killed at least eight policemen, said police Lt. Col. Saad Abdul Hamid. Seven people were wounded: a policeman, two soldiers and four civilians, he said.

At least 26 people were killed in four attacks Thursday.

In the deadliest attack, an insurgent with explosives strapped to his body joined a long line outside an army recruitment center in central Baghdad and blew himself up. At least 13 people were killed and 20 wounded in the blast, Lt. Salam Wahab said at the recruitment center.

Col. Adnan Abdul Rahman, spokesman for the Iraqi Interior Ministry, said the use of suicide bomber belts has escalated since security has been stepped up around recruitment centers and other insurgent targets. Faced with car bombings, many of these centers have become small fortresses surrounded by concrete blast walls and razor wire.

Recent raids in and around Baghdad uncovered some assembled car bombs and foiled many attacks, Abdul Rahman said. "But it is rather difficult to find out about an explosive belt put on by a person," he said.