BAGHDAD — A series of coordinated attacks struck Baghdad today, including three car bombs that blew up near government sites. At least 103 were killed and 197 wounded in the worst wave of violence in the capital in more than a month, authorities said.

A total of four attacks, which also included a suicide car bomb on a police patrol, showed the ability of insurgents to strike high-profile targets in the heart of Baghdad and marked the third time since August that government buildings were targeted with multiple blasts that brought massive bloodshed.

The bombings reinforced concerns about shortcomings in Iraqi security as U.S. forces plan their withdrawal. The U.S. military has sent some troops and forensic equipment to assist the Iraqis.

Overall violence has dropped sharply around Iraq in the past year, though insurgents have stepped up attacks at government sites in recent months. The bombings marked the most serious spate of violence in Baghdad since twin car bombs on Oct. 25 struck outside Baghdad administration offices, killing at least 155. In August, suicide bombers hit the finance and foreign ministries, killing more than 100.

Iraqi officials blamed the October attacks on loyalists to Saddam Hussein's banned Baathist Party — even bringing out three suspects on national television who gave what officials termed confessions.

But there are questions whether leaders are trying to shift attention away from a possible resurgence of Sunni insurgents led by al-Qaida in Iraq. A rise in insurgent power could be a serious blow to the government's credibility before national elections, which were set today for March 6 — a more than seven-week delay from the original mid-January date because of political bickering on the voting rules.