Back-to-back homicide bombings killed at least 60 people and injured more than 125 on Friday outside the most important Shiite shrine in Baghdad, police officials told Reuters.

The blasts are the latest in a series of high-profile attacks blamed on Sunni insurgents. On Thursday, nearly 80 people were killed in two homicide bombings in the deadliest day in Iraq in more than a year.

The bombers Friday detonated explosive belts within minutes of each other near the gates of the tomb of Imam Mousa al-Kazim, a prominent Shiite saint, located in the northern neighborhood of Kazimiyah, said a police official. Another police official said the bombers struck shortly before the start of Friday prayers as worshippers streamed in to the mosque — an important site for Shiite pilgrims.

About 90 people also were injured in the blast, said the same official.

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

The shrine has been a favored target of insurgents, most recently in early April when the a bomb left in a plastic bag near the shrine killed seven people and wounded 23.

In January, a man dressed as a woman blew himself up near the shrine, killing more than three dozen people and wounding more than 70.

Imam Mousa al-Kazim is an eighth century saint, and one of 12 Shiite saints. Hundreds of thousands of Shiites march to the shrine in Kazimiyah every year to commemorate his death in A.D. 799. Shiites believe al-Kazim is buried in the Baghdad golden-domed shrine.

The Associated Press contributed to this report.