A domestic dispute fueled a car chase yesterday between an off-duty police officer and a gun-toting father who took his child along for the ride and who fired a shot at the officer, according to police.

About 10:20 a.m., an off-duty male sergeant from the Highway Patrol was picking up a parishioner from church services near Franklin Place and Green Street when he was flagged down and told that a man nearby was pointing a gun at a woman, said police spokesman Lt. Frank Vanore.

As the sergeant approached the man, identified by police as 20-year-old Justin Ellis, of Catharine Street near 57th, Ellis jumped in a white Mercury Marquis.

Another man, who was attempting to intervene in the dispute between Ellis and the mother of his child, ended up in the car, along with Ellis' 2-year-old child, Vanore said.

Police are not considering the second man a defendant, saying he may have been caught up in the action and unable to escape the situation. It remains unclear how or why the 2-year-old was in the car.

The sergeant pursued Ellis' vehicle to Spring Garden Street, and it was on Spring Garden near Broad that the driver allegedly fired one shot at the sergeant.

Having escaped injury, the sergeant pursued the vehicle onto westbound Interstate 76. From I-76, Ellis took the Girard Avenue exit and threw his gun, which was later found by police, out of the window, Vanore said.

Ellis stopped the car shortly thereafter, perhaps because he was stuck in a traffic jam, Vanore said.

The sergeant approached the car and tried to remove Ellis but a struggle ensued, during which the sergeant discharged his gun once, police said. The shot appeared to be accidental and did not hurt anyone, Vanore said.

The child was safely recovered and returned to his mother, Vanore said.

Ellis was taken into custody and charged with two counts each of aggravated assault, simple assault, recklessly endangering another person, possessing instruments of a crime and endangering the welfare of a child.

According to court records, Ellis was charged in 2005 with possession of a controlled substance and possession with the intent to deliver a controlled substance, but the charges were dropped last year by the district attorney's office. *