ISLAMABAD, Pakistan  A blast detonated by a suicide bomber ripped through a Shiite protest, the second such attack in three days, in the southwestern Pakistani city of Quetta on Friday, killing at least 53 people, police and rescue officials said. At least 100 people were wounded.

A Pakistani Taliban commander told The Associated Press that his group carried out the attack.

Militants are intensifying their violent attacks to pressure a government that has been struggling to cope with devastating floods, described as the worst in the country’s history.

The attack was aimed at a procession of Shiite Muslims who were part of nationwide marches to observe Al Quds Day, an annual protest to express solidarity with Palestinians and condemn Israel.