At least 25 people have been killed in two separate insurgent bombing attacks in Iraq targeting the police force.
The attack continues the pattern of targeting Iraqi police
In the northern city of Mosul, police were waiting to collect their wages at a hospital when a suicide bomber called them around him and detonated his bomb.
At least 12 people were killed in the blast, which left a huge crater.
Thirteen police recruits died in a bomb attack in Baquba - making Monday the deadliest day of violence since the Iraqi elections eight days ago.
Separately, one US soldier was killed and two others were wounded in a roadside bomb attack in northern Baghdad.
Police spokesman Saad Aziz said the attack in Mosul happened inside the compound of the Jumhouri Teaching Hospital, where police were gathered.
"The bomber was wearing a long coat. He called the young men over to him to gather around him and he set off the bomb," he told AFP news agency.
The organisation of militant Abu Musab al-Zarqawi said it had carried out the attack, though this has not been independently confirmed.
Also on Monday, insurgents shelled a police station in Mosul, killing at least one civilian and wounding three others.
Mosul, Iraq's third largest city, has seen surge in violence since the campaign by US and Iraqi forces to pacify the city of Falluja.
The Baquba blast occurred as a group of men were queuing outside the Diyala provincial police station to join the force, just before 1100 local time (0800 GMT).
Iraqi officials said a car bomb was set off. It was the latest of a regular series of attacks in the town.
Pattern of violence
About 50 civilians, police and US forces have been killed in insurgent violence since the 30 January elections.
Baquba has been a regular target for insurgent violence
There have also been several incidences of hostage-taking in recent days, with four Egyptian engineers abducted in Baghdad on Sunday.
Two days earlier, Italian journalist Giuliana Sgrena was seized in the capital.
An internet message by a militant group threatened to kill Ms Sgrena by Monday if the Italian government did not withdraw its troops from Iraq.
The BBC's Jon Leyne in Baghdad says the insurgents appear to be following a familiar pattern of attacks, after a lull following the poll.
The counting of votes continues, with early indications point to a landslide victory for the Shia-led United Iraqi Alliance list, which is backed by senior cleric Grand Ayatollah Ali Sistani.
Partial results in 13 provinces showed that the UAI had approximately 2.3 million votes, with an alliance of Kurdish parties in second place with 1.1 million votes.
The bloc led by interim Prime Minister Iyad Allawi has received about 620,000 votes so far, election commission spokesmen said.
The alliance has emerged as a surprise early leader in the count in Salah al-Din province, north of Baghdad, with the Kurdish alliance in second place. Correspondents say the partial result suggests a very low turn-out in the Sunni-majority province.
Provisional election results are expected later this week.