LOS ANGELES (CBS SF) — A tip from a parole officer led to the arrest Sunday of a man that Los Angeles police said was the “main aggressor” in the attack on San Francisco Giants fan Bryan Stow outside Dodger Stadium after the rival teams’ season opener.

Stow, a 42-year-old paramedic and father of two from Santa Cruz, was attacked in a stadium parking lot on March 31 in a brutal beating that left him with brain damage — prompting an outpouring of support for him and outrage in the sports world and beyond.

READ MORE: News Crew Security Guard Shot In Oakland Dies From Injuries

Police said in a statement Sunday night that 31-year-old Giovanni Ramirez of Los Angeles had been booked for assault with a deadly weapon and was being held on $1 million bail.

LAPD Chief Charlie Beck said Ramirez was taken into custody early Sunday morning as detectives and SWAT team members working on a tip from a parole officer served a search warrant at an East Hollywood apartment building.

Sources told CBS Los Angeles that Ramirez has a prior criminal record including violent incidents and was out on parole at the time of Stow’s attack.

Police said Ramirez had become familiar to many throughout Southern California as “Suspect 1” from the flyers with the suspects’ sketches. They described him as having a bald head, goatee, and tattoos on his neck.

An emotional Beck hailed the work of 20 full-time detectives who he said had pursued more than 630 leads in the case so far, cumulatively working more than 6,000 hours.

“This is a huge step. But this investigation is in its very early stages,” Beck told reporters Sunday afternoon outside the stadium. “There are at least two other suspects who we are actively looking for.”

Stow’s mother said L.A. police called her family earlier Sunday to tell them about the detained suspect.

“I’m just actually shaking because when the detective called me this morning… it was a little bit before 8 o’clock. He wanted to tell me the breaking news, cause he said it’s gonna be on the news so he wanted us to hear it from them that they had made an arrest,” Ann Stow said in an interview with KCBS radio.

“I could not wait to get off the phone to call my daughters and obviously, they started sending out mass texts to all family and friends that an arrest had been made,” Ann Stow added.

KCBS Interviews Ann Stow:

READ MORE: UPDATE: 2 Men Shot Outside South Bay High School Football Playoff Game

San Francisco Mayor Ed Lee said after hearing the news Sunday that he called Los Angeles Mayor Antonio Villaraigosa to express his thanks for authorities’ efforts and to congratulate him.

“We’re very very happy and excited. Hard work, around the clock, brought us to this (moment) today,” Villaraigosa indicated. “I’ve said for sometime this was an absolute priority of ours. Our officers have been working day and night to find these individuals and I said back then that we would and we have.”

Giants team officials also released a statement commending the LAPD and thanking “the community for its tremendous support for the Stow family during this difficult time.”

Giants president Larry Baer added that the arrest was “comforting” for the team and its fans, and said that his best hope was that the incident might spur more civility at sporting events.

Giants fan Les Wong, 37 of San Francisco, celebrated the news as he headed to the Giants/A’s game at AT&T Park on Sunday afternoon.

“It’s good to hear that they caught someone. That kind of thing doesn’t belong in sports,” said Wong, who was wearing a Giants hat and Giants t-shirt. “I’m glad to hear there is going to be some sort of justice.”

KCBS’ Chris Filippi Reports On Fan Reaction:

Stow, who was wearing Giants gear, was leaving the game at Dodger Stadium with two friends when he was attacked — repeatedly punched and kicked by two men wearing Dodgers gear as they yelled profanities about the Giants.

Stow had been in a medically-induced coma for nearly two months since the attack, and was transferred last week from Los Angeles County-USC Medical Center to San Francisco General Hospital. Doctors reported that Stow has now been able to open his eyes, but he remained in critical condition.

Police said Stow’s attackers fled in a car driven by a woman in her 20s. More than 200 billboards with images of the suspects were put up around Southern California in an effort to track down the assailants, and a reward of up to $200,000 was offered for their arrest.

The LAPD’s Beck said of that even with Sunday’s arrest, “this job is only half done” since two remaining suspects were still at large, and others who spoke at the news conference echoed the same.

“The woman who was driving, you need to give yourself in. The other coward who did this, you need to give yourself in,” said L.A. City Councilman Ed Reyes, who represents the area that includes Dodger Stadium.

MORE NEWS: COVID: Expert Says New Omicron Coronavirus Variant Likely Already in U.S.

(Copyright 2011 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The AP, CNN, and BCN wire services all contributed to this report)