Paul Pagan (l) was charged in the murder of 54-year-old Peter Fabbri. View Full Caption DNAinfo/Alex Nitkin

CHICAGO — Prosecutors charged a two-time convict Monday in this weekend's slaying of a suburban man who came Downtown with his mother and girlfriend for a wine tasting, only to be shot in the head during a street quarrel near Millennium Park.

The murder followed a heated argument on the street about religion, but the alleged shooter had nothing to do with that argument, said Chicago Police Cmdr. Brendan Deenihan.

Instead, Paul Pagan intervened in the heated argument, pulled out a gun and shot Peter Fabbri, 54, of west suburban Berwyn, Deenihan said.

Police said Fabbri and his group had left a wine tasting event and encountered a group preaching about religion on the street. Fabbri's group, described by Deenihan as Christians, found the message being delivered to be hateful and got into an argument with the other group, which was passing out pamphlets.

The argument escalated, and that's when Pagan rode up on a bike. He started arguing with Fabbri, an argument that turned physical, police said. He then pulled out a handgun and shot Fabbri, Deenihan said.

Pagan was not affiliated with either group. Fabbri's group tried to detain him, but Pagan got back on his bike and rode off. A quick response by police, however, led to Pagan's arrest, he said.

"The people who were on the scene who were part of this message, when the gunshot went off they immediately left the scene...and we haven't been able to locate a pamphlet or flier," Deenihan said.

Pagan, 32, was charged with Fabbri's murder, Chicago Police spokesman Anthony Guglielmi announced via Twitter Monday afternoon.

BREAKING: CPD has charged 32yo gang member & 2 time convicted gun offender Paul Pagan in Millenium Park murder. Press briefing 3pm @ HQ pic.twitter.com/tEVFLS4PHG — Anthony Guglielmi (@AJGuglielmi) September 26, 2016

Fabbri had been on life support since the Saturday night shooting near Millennium Park. His family said he was taken off life support Sunday night.

Police said Fabbri was shot twice, once in the head and once in the stomach. But his niece, Nina Parks, wrote on GoFundMe that he was shot three times, including twice in his stomach.

Pagan is a "gang member & 2 time convicted gun offender," Guglielmi said.

"All of us who can search police records and news clips can point to a reprehensible murder or shooting that happens and say we wish we had a way to hold a repeat offenders accountable for their violence acts," Chicago Police First Deputy Supt. Kevin Navarro said at a Monday news conference. "By failing to serve sufficient penalties, the offenders have nothing to fear."

Pagan faced two charges of aggravated assault with a deadly weapon in August 2015 and in May of this year, police said.

Joe Ward shares details on the shooting near Millennium Park.

He was taken off life support at Northwestern Memorial Hospital Sunday night, Parks said.

He was pronounced dead 5:53 p.m. Sunday, according to the Cook County Medical Examiner's Office. His address was listed in suburban Berwyn.

The two women Fabbri was walking with at the time of the shooting were his mother and girlfriend, Parks said. They had gone Downtown for a wine tasting.

The family launched a GoFundMe campaign seeking money to help cremate Fabbri. Nearly $2,400 had been raised as of Monday morning. Donations can be made here.

"My uncle ... was a huge-hearted man and was always there for anyone if he could be," Parks wrote on the fundraiser page.

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