Baghdad, Iraq ? Suicide car bombs struck Iraqi police and Kurdish militiamen in Baghdad and northern Iraq on Saturday, killing at least 16 people, wounding dozens, and again demonstrating the lethal reach of Iraq’s insurgency just weeks ahead of crucial elections.

The U.S. commander in Iraq, Gen. John Abizaid, acknowledged that the country’s homegrown forces aren’t yet up to the task of ensuring secure elections, requiring the planned increase in U.S. troops. More than 42 Iraqis have been killed in the past two days alone.

But U.N. special envoy Lakhdar Brahimi criticized the military’s hardline approach to the insurgency and said credible elections could not be held Jan. 30 under the current conditions.

“It’s a mess in Iraq. The international community, hopefully with the Americans, must help the Iraqis to clean up the mess,” he said.

Meanwhile, the insurgents pursued their deadly campaign against American troops. Two U.S. soldiers were killed by roadside bombs in Baghdad and north of the capital Saturday, and the military said two other Americans died the day before in suicide car bombings of their post near the Jordanian border.

With the country still so unstable and elections eight weeks away, the U.S. military plans to increase its troop strength from 138,000 to about 150,000 by mid-January — slightly more than during the 2003 invasion that toppled Saddam Hussein’s regime — in an attempt to keep order during the vote. The primary concern is Iraq’s Sunnis, who generally oppose the vote and are believed to be fueling the insurgency.

In candid remarks, Abizaid admitted the troop increase wasn’t what Washington had envisioned.

“It had been our hope that we would be able to have a combination of increases that mainly were Iraqi troops’ increases,” Abizaid, the head of U.S. Central Command, said.