Baghdad, Iraq (CNN) -- The death toll from three suicide attacks in the central Iraqi city of Baquba climbed to 33 on Thursday, police said.
Forty-two other people were wounded in Wednesday's bombings.
The first two explosions involved suicide car bombs. One struck a government office near a police checkpoint in western Baquba.
Two minutes later, a second suicide car bomb went off near the party headquarters of former Prime Minister Ibrahim al-Jaafari in the central part of the city, home to many such political offices.
About an hour later, a suicide bomber walked into the emergency room of a Baquba hospital and struck as casualties from the first two attacks were being rushed in.
The blasts came days ahead of Sunday's parliamentary elections -- the second to be held since then-President Saddam Hussein was removed from power during the U.S. invasion in 2003.
U.S. and Iraqi officials have warned of large-scale attacks in the run-up to the voting. And al Qaeda in Iraq's umbrella group, the Islamic State of Iraq, has promised to disrupt the elections.
Baquba, the capital of Diyala province, is about 37 miles (60 km) north of Baghdad. Sunni insurgents continue to fight U.S. troops and Iraqi security forces there.
CNN's Mohammed Tawfeeq and Jomana Karadsheh contributed to this report.