A string of attacks Saturday against Shiite pilgrims in eastern Baghdad killed five, the latest round of violence to strike worshippers during a revered mourning observance.

Insurgents have targeted Shiite pilgrims, killing dozens and wounding more than 100 this week in an attempt to re-ignite sectarian violence.

The attacks began Saturday morning when a bomb was planted near a tent that offered drinks and food to pilgrims, a police official said. The blast killed three and injured 16, he said. A medical official confirmed the casualties.

Hours later, a bomb exploded near a line of minibuses parked in eastern Baghdad that were carrying pilgrims to the holy city of Karbala, killing two people and injuring seven, said police and medical officials.

In a separate incident minutes later, an attacker hurled a hand grenade into another tent full of pilgrims in another part of eastern Baghdad, injuring six, said a police official.

All the officials spoke on condition of anonymity because they were not authorized to release the information.

Hundreds of thousands of Shiite pilgrims are making their way to the southern city of Karbala for Ashoura. The ten-day mourning period culminates Sunday, marking the anniversary of the 7th-century death of the Prophet Muhammad's grandson, Imam Hussein, who was killed in a battle near Karbala.

The outcome of the battle caused the split between Shiites and Sunni Muslims.

During Ashoura, pilgrims march through the streets beating themselves with fists and whips to demonstrate their grief.

Portions of the Ashoura observance were banned under former dictator Saddam Hussein, who barred walking to Karbala and other rituals.

Iraq's government has deployed 25,000 security personnel in and around Karbala to protect the pilgrims.

An explosion Thursday in Hillah, south of Baghdad, killed 19 people at a busy bus terminal where pilgrims were gathering, police said. A children's Ashoura procession was struck Friday in Baghdad's Sadr City by a bomb that killed six and wounded 17.