The clean-cut Brown, 19, one of the fastest-rising stars of the last two years, was free on $50,000 bail, a day after the couple hurriedly canceled separate performances at the Grammy Awards in Los Angeles.
Both the Brown and Rihanna camps were silent on Monday. Police sources told the Los Angeles Times and celebrity Web site TMZ.com that the woman who reported she had been attacked by Brown in the early hours of Sunday was 20-year-old Rihanna, singer of hits "Umbrella" and "Disturbia."
Wrigley said in a statement it was "concerned by the serious allegations" made against Brown, who was booked by police on suspicion of making a felony criminal threat.
The company said that while Brown should be afforded due legal process "we have made the decision to suspend the current advertising featuring Brown…until the matter is resolved."
Brown, who was competing against Rihanna in a Grammy category, was a spokesman for Doublemint gum and his hit song "Forever" was part of that advertising campaign.
Brown is also a pitchman for the long-running Got Milk? campaign, in which celebrities are photographed with a milk mustache. The Milk Processor Education Program said his participation was scheduled to end this week, as planned.
"The Milk Mustache campaign is taking the allegations against Chris Brown very seriously," the Washington, D.C.-based trade group said in a statement. "We are very proud and protective of the image of the Milk Mustache campaign and the responsible message it sends to teens."
The incident appeared to be out of character for Brown, who has been dating Barbados-born Rihanna for about a year and helped produce her album.
She was variously reported to have been left bruised, bleeding and even bitten in the attack, which took place shortly after she and Brown left a pre-Grammy party in Beverly Hills on Saturday night.
Police said the woman "suffered visible injuries" in the incident, which started in a car and continued as both parties got out. Los Angeles prosecutors are considering whether to formally charge Brown, who could face up to three years in prison if convicted, legal sources said.
Celebrity Web site Radaronline quoted an unidentified eyewitness who said she had seen Rihanna being treated at the Cedars-Sinai Medical Center on Saturday.
"Rihanna was clearly very upset by what happened and I could hear her screaming. Rihanna was trying to get her point across about something. She sounded like she was crying," the eyewitness told Radaronline.com.
Rihanna’s publicist issued a brief statement on Sunday saying: "Rihanna is well. Thank you for concern and support."
Fans of both Rihanna and Brown, who made his name at age 16 with the single "Run It", were shocked by the incident.
People magazine pondered what had gone wrong, calling it a "Fairy-tale romance gone awry". One of hundreds of postings on the Us Weekly Web site said; "I just don’t understand. it’s so out of character of him. i really want to know the real story. i just can’t believe he beat some girl. doesn’t seem like him what so ever."