Police in Iraq have found nine severed heads, wrapped in plastic bags and left in a fruit box by the side of a road.
Tuesday's gruesome find followed a similar discovery on Saturday
The heads were found near Baquba, north of Baghdad, where police made a similar discovery three days ago. The identity of the latest victims is unclear.
Meanwhile, Iraq's health ministry says the bodies of 6,000 people have been brought into Baghdad's main mortuary this year, most of whom died violently.
New figures show a peak last month with 1,400 bodies brought in.
This was an increase of almost 40% from the numbers received in January.
But the true death toll from the mainly sectarian violence could be a lot higher because many bodies are not taken to the mortuary or are never found, the BBC's Andrew North in Baghdad says.
Also on Tuesday, the Iraqi interior ministry said an internal investigation was under way into the kidnapping of 50 people in central Baghdad on Monday.
Some of the heads discovered in Baquba were blindfolded and already decomposing, suggesting that the killings had taken place a few days before, police said.
Baquba lies in a mixed Sunni Arab and Shia province where attacks against civilians have been common.
Monday's kidnapping in Baghdad was reported to have been carried out by men in police commando uniforms.
The incident took place on Salihiya street, which is lined with transport firms offering travel around the country and to Jordan and Syria.
The interior ministry, which oversees the police, has denied that its forces were involved.
Sunni Iraqi politicians, who have long accused the Shia-dominated police force of involvement in sectarian killings, have alleged police were behind the abductions.
Separately, Iraqi Prime Minister Nouri Maliki said on Tuesday that he would release 2,500 prisoners, starting on Wednesday as a gesture, of "national reconciliation".
Mr Maliki has yet to appoint defence and interior ministers
He said those to be released would not include supporters of the ousted President, Saddam Hussein, or anyone who had Iraqi blood on their hands.
He said the prisoners would be released from US-run detention centres and Iraqi prisons.
"We hope they will abide by not violently objecting to the political process. This is a strong move which will encourage others," Mr Maliki said.
Our correspondent says Mr Maliki hopes that by announcing such a large release in one go, it will help win over more members of the Sunni community and undermine support for the insurgency.
Iraq's Sunni Vice-President, Tariq al-Hashemi, was closely involved in deciding who should be set free.
In April, the UN's human rights official in Iraq, Gianni Magazzeni, said the Iraqi authorities were illegally holding thousands of people.
Almost 29,000 Iraqis are believed to be in US and Iraqi custody across the country, most of them Sunnis detained in connection with attacks on US and Iraqi forces.
Mr Maliki has previously said his top priorities are to expand the participation of all Iraqis in the political process, and to improve the security situation.
But he has been unable to fill the two key security posts in his cabinet - the ministers of defence and interior - because of disagreements among political groups.