At least 27 people, possibly many more, have been killed by an explosion at a disused oil pipeline in southern Iraq.
The oil pipeline explosion caused a huge fire
A police spokesman said people had been siphoning fuel from the pipeline in an industrial zone south of Diwaniya, 130km (80 miles) south of Baghdad.
Casualty reports varied widely - one put the death toll at 74. Police said a huge fire was hampering rescue efforts.
In a separate development, police found more than 20 bodies at two sites in Baghdad. All the victims had been shot.
Officials say the cause of the blast in Diwaniya is still being investigated.
Witnesses told Reuters the explosion happened at about 2300 local time (1900 GMT) on Monday, when a large group of people were taking fuel from two pools.
A unnamed police source quoted by Reuters news agency said 50 people had been killed, while AFP quoted a health official saying 74 died. However, the provincial governor put the toll at 27.
Some people were left horrifically injured by the blast. "Some of the wounded have burns on 75% of their bodies," Hamid Jaafi, a health official in Diwaniya told Reuters.
He said that besides those confirmed dead, relatives said dozens of people were still missing.
Government officials said the pipeline, which used to carry petrol to the capital, had been out of operation since 2003.
But a defence ministry official said it still held residues of fuel and residents often cut holes in it to siphon off petrol, which is in short supply despite Iraq's wealth of oil deposits.
After the bodies were found in Baghdad, police said the victims had been bound and shot, and some bore signs of torture. Their identities are not known.
Eleven of the bodies were found near a school in a south-western district of the capital. At least 10 other bodies were dumped behind a Shia mosque in the west of the city.
The deaths come at a time when US and Iraqi security forces are engaged in a new security operation aimed at reducing the level of violence in the city.
Also on Tuesday, insurgents killed two Shia militiamen in the city of Baquba north of Baghdad.
Iraqi police told the AFP news agency the militiamen were killed in an attack on the office of radical cleric Moqtada Sadr.
The US military in Iraq announced on Tuesday that two US soldiers died in Iraq - one in fighting in Anbar province and the second from injuries sustained in a vehicle accident.