Argentina's Congress approved a controversial pension reform bill yesterday that has prompted violent protests and a general strike. Lawmakers passed the measure in the lower house in a 128-116 vote after debating for more than 12 hours.

The legislation, which had already cleared the Senate, would change the formula that pension benefits are calculated based on inflation instead of wage growth and tax contributions. It's a key part of a series of economic changes pushed by the government of President Mauricio Macri to reduce Argentina's high deficit and attract investments.

But critics complain the bill will cut pension and retirement payments as well as aid for some poor families.

About 150 people were injured and about 60 were arrested when clashes between police and demonstrators broke out Monday outside the Congress building in Buenos Aires. Some retirees who were protesting the measure were caught up in the middle of the violence when some demonstrators hauled rocks and gasoline bombs, and riot police responded with tear gas and rubber bullets. Others banged on pots in protest in several neighborhoods of the Argentine capital late into the night.

Argentina's largest union also called a 24-hour general strike that is grounding hundreds of flights. The measure was initially set to be debated on Dec. 14, but the session was suspended because of violent clashes.

Since taking office in 2015, Macri has vowed to rein in government spending and revive Argentina's lagging economy. But his ordering of job cuts and the cutting of utility subsidies has fueled labor unrest.In October, the conservative leader announced that he would seek more sweeping changes in tax, education and labor after his governing coalition scored a resounding victory in congressional elections.