By Jim Muir
BBC News, Baghdad
Iraq's government says that 355 Iraqis were killed in April, making it the bloodiest month so far this year.
The bulk of the deaths came from a number of big explosions, and the death count did not include at least 80 Iranian pilgrims killed in Iraq.
April was also the deadliest month for US troops since September, with 18 soldiers killed.
The casualties are nowhere near the 2006-07 levels when the insurgency and sectarian strife were at their peak.
The figure of 355 Iraqis killed in April is mainly made up of 290 civilians, but it also includes 65 soldiers or policemen, who are often the targets of attacks.
The figures, issued by three Iraqi ministries, showed a 40% rise over March.
This is mainly because of several very big bomb attacks, including four in the space of just two days, in which at least 150 people were killed.
In both 2006 and 2007, the average monthly death toll for civilians alone was over 2,000.
Nonetheless, the trend shown by these and other casualty estimates since January this year has been creeping month by month, and that has to be a worrying development, as American troops start withdrawing.
The same trend seems to be reflected in US military casualties.
Eighteen Americans died in April, the highest number since last September, but also, far below their worst months in 2006 and 2007, when more than 100 died each month.
Iraqi leaders and US military officials are playing down the upward trend.
They say the bomb devices are cruder than in the past, and they are failing to stir up the kind of sectarian reaction which happened before.