Investigators still don’t know why a Paterson man opened fire on his estranged wife and their two young sons on a busy street, killing one boy.

Saturday’s rampage ended when Edelmiro Gonzalez was confronted and shot by an off-duty city police officer. The officer opened fire after Gonzalez refused an order to drop his weapon, and Gonzalez later died at a nearby hospital.

Detective Lt. Ronald Humphrey said Gonzalez approached his family and first shot his 7-year-old son, who died at the scene, then chased down his 11-year-old son and shot him. Gonzalez then chased his wife past a fast food restaurant — where the off-duty officer was getting breakfast with his own son — and shot her once in the shoulder.

The woman and her older son remained hospitalized Sunday in critical condition.

Copyright 2009 The Associated Press.